The modern worker has a quiver full of productivity tools. You can choose from umpteen task list apps like Remember the Milk or Wunderlist. You can talk to your phone to arrange a meeting or reply to a text message. If you have a cluttered email inbox, there are apps like Mailbox that help you sort, archive, and curate your messages in seconds.

Yet, why is it that it's still so hard to get things done? You start out with good intentions--get to inbox zero, prep for a meeting, and check off at least five of the tasks on your to-do list. When the clock finally hits 5 p.m., you've failed to do any of the above and wonder what, in fact, you did do for the past eight hours.

The problem might not have anything to do with the tools. It might be how you use them. There are a few hallmarks of highly ineffective people. Here are seven.

1. You always finish your task list.

Apps like Remember the Milk encourage you to finish your tasks for the day. That's why the apps exist. Yet, as Marissa Mayer explained in a talk with last year, checking every item off your list is a sure sign you are being unproductive. (It might also imply you just enjoy completing your task list.) Truly productive people prioritize tasks and let things slide if they are not that important. They are not completists--they are productivists.

2. You always answer the phone.

I know a few colleagues who seem to always pick up the phone. One friend who runs an insurance agency tells me his theory: Letting a call go to voice mail tells the customer he or she is not that important. Callers want to reach a live human. In some ways, it seems effective--especially if you are the one taking the sales orders. But it's not. In truth, research indicates it is much more effective to focus on what you are doing at the time. A call is an interruption in most cases--it means you are suddenly multitasking, and that means you are slowing down. Finish your task, then call back.

3. You use the "touch once" principle.

Here's one I learned many years ago. Apparently, when it comes to document management or your email or social networking, it is more effective to deal with an issue as soon as it arrives. Someone hands you a contract, it's best to sign it then and there. Otherwise, the time invested in receiving the document, filing it, signing it, and handing it back in will multiply. But is that always true? With email and my social feeds, I don't always "touch" once. In fact, I rarely do. Most incoming messages are not that important--and neither are most paper documents.

4. You see communication as a one-way street.

This is a huge problem for ineffective people. You wonder why you can't get anything done or why you can't motivate people. Look in the mirror. In most cases, those who have the most trouble communicating are the ones doing all of the talking. You can't really understand what people want if you never shut up and listen to them. Worse, being a one-way communicator means people are less likely to give you a hand. Listen more, and you might gain a productivity ally.

5. You block all interruptions.

I mentioned how taking every phone call is bad for your productivity. It means you are not finishing the task at hand. Yet, having a strict rule about no interruptions is also ineffective. Why is that? As you probably know, interruptions can work like fuel for your brain. You are finishing up a task and then--wham!--someone barges into your office. Those serendipitous moments of the day can inspire new ideas. Also, being effective sometimes means letting interruptions steer you in a different, possibly better, direction. Just make sure you're selective about which interruptions you let dictate your next move.

6. You're in it to win it.

Ineffective people are looking for the "win" in everything they do. In the book Give and Take: A Revolutionary Approach to Success, by Adam Grant, the idea of always "taking" for yourself turns out to be counterproductive, because you fail to realize the role other people play in order for you to succeed. Highly effective people direct their efforts toward a group win; they are part of an overall team effort. It takes a village to be productive.

7. You are solely focused on being effective.

Yes, there is great irony in this one. The more you focus on being effective, the less effective you will be. In my job as a writer, I often think the goal is to be as efficient as possible. In the very act of focusing on my own efficiency and knocking things off my list, I complete tasks prematurely, before I have enough information. It's a kind of tunnel vision that hampers my ability to see the bigger picture. In many ways, it is better to focus on relationships with co-workers, or on whether your company is offering a better service to the world, or even if you are getting home in time for supper. That more holistic view, in the end, can give you perspective on what's really important.