Sales are the lifeblood of any business -- but selling is hard. When you're struggling to find new prospects, it's easy to get down. When you're struggling to turn prospects into customers, it's easy to get discouraged. When that happens, you need to get yourself -- and your sales -- back on track.

But that inspiration and motivation doesn't only have to come from within. Why not gain inspiration and motivation from successful people who have been there, done that... and done it extremely well?

The following is from Ryan Robinson, a content marketing consultant to the world's top experts and growing startups.

Here's Ryan:

We all have our off days. That's a given.

But a string of days with low motivation can do more than just put us in a slump. It can seriously impact our sales targets and cause unnecessary stress and anxiety. So when you start to feel yourself sliding down that path, it's a good idea to look at people who've been there and made it to the other side and see how they did it.

These quotes are not a replacement for hard work, but rather snackable pieces of actionable inspiration to put you back on track when you lose motivation.

And because I believe progress is measured in action, each is paired with a specific action item you can take today to boost your productivity, give you a virtual high-five when you're feeling low, and create real results for your business.

1. "Don't try to be a man of success, try to be a man of value." Albert Einstein

What it means:

There's a reason people react so negatively when they feel a salesperson is being too 'sales-y'. A successful sale doesn't talk about you, but rather what you can do for your potential client. How do you add value to their lives? How is working with you going to transform them? There's more to what we do as salespeople than just the numbers.

Action you can take today:

Instead of obsessing over stats, become a great storyteller. Show your prospects the story of their lives before, during, and after they become your client and the transformative value that you're adding. Nail down this value story before jumping on your next call and become a 'man of value'.

2. "You can't turn a 'no' to a 'yes' without a 'maybe' in between." Francis Underwood

What it means:

The path to a sale is never A to B. There's a whole alphabet between your first conversation and the close. Don't get discouraged when you hit a wall asking for the close. Think how that 'maybe' is really just a 'yes' in disguise.

Action you can take today:

Create a list of common concerns that cause your prospects to answer with a 'maybe' and why those concerns are unfounded. Knowing these and being able to explain them simply, clearly, and confidently will help you keep the conversation moving on the path to a yes. 'Maybe' is where great salespeople live. They know that anything other than a flat out 'no' is a step towards a yes.

3. "You are what you repeatedly do. Excellence, then, is not an act, but a habit." Aristotle

What it means:

How you choose to live your days is how you choose to live your life. Are you willing to put in the time every day to reach the level of success you truly want? Are you willing to miss that dinner or not go out for drinks because you're working towards something bigger? These are the choices that define who you are and how successful you'll be as a salesperson.

Action you can take today:

Focus on habits, not goals. Frame your day around incentivizing and rewarding yourself for repeating a habit, like making your 40 calls for the day, instead of putting a daily dollar amount on a pedestal. Create a repeatable process for yourself which you know will get you where you want and that you can do every single day without fail. This way, you're focusing on actions you control rather than putting all the pressure on results that might not come.

4. "You just can't beat the person who never gives up." Babe Ruth

What it means:

Simply put, success comes to those who refuse to quit. A little less simply put, behavioral economists studying human motivation discovered something called Time Inconsistency--which is the brain's tendency to value immediate rewards more highly than future rewards. Unfortunately, selling is less about winning every little skirmish and more about winning the war. This means pushing through down days, forcing yourself to do the work even when you aren't 'feeling it', and never, ever giving up.

Action you can take today:

Take a step back and look at the bigger picture of your sales strategy. It's easy to get lost in the day-to-day of sales and lose sight of where you want yourself to be in a month, a year, hell, even 10 years. Commit to the long-term vision of what you want to achieve and never give up. Use that vision of future you to inspire you along the way when life gets you down.

5. "Nothing diminishes anxiety faster than action." Walter Anderson

What it means:

We're all procrastinators at some point. But ironically, the guilt and frustration we feel from not starting is often worse than the pain of actually doing work. The anxiety we feel when faced with a huge list of prospects or massive sales goals can seem insurmountable, but something amazing happens once we actually start working: The fear goes away and the to-do list all of a sudden seems more doable.

Action you can take today:

List the one thing you can do right now, no matter how small, that will help you move forward. Is it as simple as making that first call? Or replying to an email? Try to get even more specific. Instead of saying, "I'll call 5 prospects on Wednesday," say, "I'll call 5 prospects on Wednesday between 10-11am." Break down bigger tasks into small items you can easily get started on and watch your motivation skyrocket.

6. "Success is never owned; it is only rented--and the rent is due every day." Rory Vaden

What it means:

In sales (and in life) there's never a good time to rest on your past achievements. The success you have today came from what you did yesterday. And if you sit back and stop doing what got you here, it'll go away just as quickly as it came. You owe it to yourself and your business to put in the work every single day and keep paying your dues.

Action you can take today:

What's the rent that you paid in the past that allows you to live in the success of your present? Was it dedication? Was it taking risks? Was it constant education and personal growth? Whatever it was, start your day by making a big payment in that rent. Recognize the skills and qualities that got you where you are today and repeat them daily. Write them down and make sure you set aside time for them every single day.

7. "I fear not the man who has practiced 10,000 kicks once, but I fear the man who has practiced one kick 10,000 times." Bruce Lee

What it means:

What's more important: To be a jack of all trades or a master of one? There will always be some new tool, task, or other distraction that wants to take your attention away today. But every second spent on an unimportant task is a second taken away from working towards mastery. Focus is our greatest asset on the path to success.

Action you can take today:

What's your 'one kick'? What skill or technique, if mastered, would bring you the biggest level of success? Take a moment and think about what you put your energy into every day and whether or not you're working on the right skills and tasks. Could there be new products, apps, or services that could help increase your output or effectiveness if employed in your day-to-day? In the past, I've gone so far as to set a reminder every few hours to ask me if I'm working on the right thing at this moment or if I've been distracted again. Once a month, I set aside an hour of time on my calendar to research new product management tools and look for ways I can implement more effective processes into my workflow. Make yourself a force to be reckoned with.

8. "Pressure is a privilege." Billie Jean King

What it means:

Feeling the weight of the world on your shoulders? Guess what, that's a good thing. Being pressured means you're in a position where the actions you take matter. You've set goals that are challenging. You're motivated to be better than you are today. Pressure is just a byproduct of your own success.

Action you can take today:

Create a 'small wins scrapbook'--a collection of recent successes that you can look back on to remind yourself just how far you've come and why you're feeling pressured to do more today. It's all too easy to just move on after hitting a goal or making a sale without taking the time to appreciate the work you've done. Take that time to celebrate the small wins and value what you do every single day, which is doubly important in the workplace if you're managing a sales team that needs positive reinforcement and fresh incentives on a regular basis.

9. "Change before you have to." Jack Welch

What it means:

If you keep doing what you've always done, the best you'll get is what you already have. Unfortunately, the human brain is hardwired to take the path of least resistance, which more often than not means sticking to business as usual, even when you know that changing now will help you in the future.

Action you can take today:

Write down the one thing in your heart you know you need to change to make your life and your career better in the future. This might be something you've known for a long time but haven't felt the need to act on because there's not enough pressure in your environment to make you feel like you have to. Now, tell yourself this one thing is going to destroy your career. Every day, look at that one thing and ask yourself 'Do I really want to wait until I have to do this? Or do I want to be the person I want to be on my own terms?'

10. "If you can't explain it simply, you don't understand it well enough." Albert Einstein

What it means:

It takes a deep understanding to be able to create something simple. Think of Steve Jobs, who famously made Apple engineers make every function on the original iPod accessible in 3 clicks, just because he knew that simplicity was the key to massive sales. I think it worked out pretty well for him.

Action you can take today:

Test your pitch's 'simple factor' by taking it outside your bubble. Call up your parents or partner or even a friend in a totally different profession and try it out on them. Do they know what you're talking about? Can you answer questions that come up that you might think are 'obvious'? Can you make it as simple as possible?

11. "Everything we want is on the other side of fear." George Addair

What it means:

Fear is a sign that you're on the right path. Trying new things, taking risks, and going after the unknown are all scary experiences. They're also exactly what we need to do when we want to grow. We can't let something as harmless as a little fear stand between us and what we want.

Action you can take today:

Write down your biggest fears that you face every single day and imagine each one going to its extreme conclusion. Are you afraid of a large prospect turning you down? Take it one step further and imagine them yelling at you. Or calling your boss to complain. Or egging your house in the middle of the night. Imaging an extreme outcome to our fears lets us realize just how inconsequential they really are and helps us power through them.

12. "There is no such thing as failure. There are only results." Tony Robbins

What it means:

No matter what you do, the fact that you did something is more important than the outcome. Every action helps us move forward, whether it shows us the right way to act, or even just clarifies what we shouldn't be doing. The only real failure is in not acting.

Action you can take today:

This sage business advice that Tony Robbins once shared with me, can be applied to all facets of life. Change your perspective around what you see as 'failure' by realizing that each one has helped you in some way. Start by listing out your past 5 'failures'. Now write down what you learned from each one. Did a prospect turn you down because you messed up your pitch? Maybe you learned that you need to do more planning before a call or rewrite a section of your script. It might be painful to revisit those experiences at first, but as you become more comfortable spending time in your own 'failures' you'll start to realize that they are just stepping stones on the path to personal success.

13. "To be yourself in a world that is constantly trying to make you something else is the greatest accomplishment." Ralph Waldo Emerson

What it means:

Salespeople face more negativity than almost any other profession (just be thankful you're not a politician!) and it's all too easy to let that negativity make us think that we should just conform to what other people are doing. But the problem is that by emulating others, the best we can ever be is Number Two. To be truly great, you need to be yourself.

Action you can take today:

Don't focus on the negatives. Make a list of the moments when your unique selling style worked or times when you went with your gut and came out with the win. Remember there are so many factors in the selling process that are out of your control and that a 'no' doesn't necessarily mean you did anything wrong. Stick with the positives and aim for that top spot.

Motivation is a well that unfortunately runs dry sometimes. But with a few simple exercises and some changes in perspective, we can fill it back up. Use these quotes and action items as a guide to put you back on the path to success and start seeing real results again.