What is the single most valuable lesson you've learned in your professional life? originally appeared on Quora - the knowledge sharing network where compelling questions are answered by people with unique insights.

Answer by Edmond Lau, author of The Effective Engineer, on Quora:

Focus on high-leverage activities. Leverage is defined as the amount of output or impact produced per unit of time spent.

This lesson applies regardless of whether you love to spend many waking hours working or whether you're a subscriber of Tim Ferris's 4-Hour Work Week philosophy [1]. At some point, you'll realize that there's more work to be done than you have time available, and you'll need to prioritize what to get done. Leverage should be the central guiding metric that helps you determine where to focus your time.

Another rule of thumb for thinking about leverage is to consider the commonly mentioned Pareto principle [2] or the 80-20 rule -- the idea that 80% of the contributions or impact come from 20% of the effort. That 20% of work consists of the highest leverage activities. The 4-Hour Work Week philosophy requires taking this to the extreme -- assuming a normal 40-hour work week, what's the 10% of effort (4 hours) that you can do to achieve most of the gains?

By definition, your leverage, and hence productivity, can be increased in three ways [3]:

  • By reducing the time it takes to complete a certain activity.
  • By increasing the impact of a particular activity.
  • By shifting to higher leverage activities.

Some examples of professional activities that I engage in to increase leverage include:

  • Mentoring new hires. Mentoring (and really managing) is an extremely high-leverage activity. Over the course of a year, an employee will spend somewhere between 1880 to 2820 hours working (assuming 47 work-weeks and somewhere between 40-60 hours per week working). Spending 1 hour every day for a month (20 hours) mentoring or training a new hire may seem like a lot of time, but it represents only about 1% of the total time the new hire will spend working his/her first year and yet can have a significant influence over the productivity and effectiveness on the other 99% of those hours. That's why building a good onboarding process for new hires is a valuable investment.
  • Building tools and automating repetitive work. Coming from a software engineering background, one high-leverage activity that I tend to do is to build tools that reduce manual, repetitive work. I'm a little biased, but I'm a firm believer that everyone would benefit knowing a little bit about coding (see Should most young people learn to code?), primarily because there are many fields not traditionally associated with computer science where a mindset of automation would have huge efficiency gains. Moreover, the benefits of time-saving tools compound over time, enabling workflows that previously weren't possible. Don't do what a machine can do for you.
  • Invest in learning and in continuously improving. This falls in the bucket of "important and not urgent" tasks that Steven Covey describes in his time management matrix in The Seven Habits of Highly Effective People [4, 5]. Learning never seems like an urgent task, and it's easy -- if you don't budget time for it -- to allow unimportant interruptions to dictate your schedule. However, learning is what lets you improve your work productivity and increase the opportunities available, so it's a big high-leverage activity. Adopt a growth mindset, and start investing in yourself.
  • Actively prioritizing tasks based on estimated impact. When I worked on user growth at Quora, there were probably hundreds of things that I could have worked on at any given time that might have moved our metrics up and to the right. Deciding what I to work on next that would be the highest impact required regularly reviewing (I did this at least weekly) what needed to get done and having the data to guide the decision-making.
  • Holding tech talks and writing guides to bring new hires on board. At Quora, each new hire goes through a series of tech talks and a set of codelabs. Inspired by Google's training regimen, codelabs are documents that explain core software abstractions and concepts that we use, discuss the rationale for why we designed and used them, walk through the relevant code in the codebase, and provide a set of exercises to solidify understanding. These took many people on the team many hours to write, but they provide a scalable and reusable resource that allow new hires to start on a consistent foundation and cut down the amount of time that each individual mentor needs to spend teaching the same concepts.
  • Pushing back on meetings without an agenda or meetings that you don't really need to be a part of. Poorly run meetings are negative leverage because they waste people's time. Avoid those. A corollary to this is defining and setting agendas for meetings that you hold so that you don't waste other people's time.
  • Spending time on interviews and improving interview processes. Conducting interviews is a huge amount of work. Interviews interrupt your workday, and the hours spent talking with candidates, writing up feedback, and debriefing all add up to considerable amounts. However, making sure that you're hiring the right people, that you have a good process in place, and that people you hire are people that you would be excited to work with is essential to building a strong team and a strong product. There have been many weeks where I've interviewed 4 candidates per week, and I think my personal record during the height of the recruiting season was doing 20 interviews in 20 consecutive workdays.
  • Using open-source tools when they meet your needs. There's no sense in re-inventing the wheel if someone else has already built what you need.

If you're looking for other high-leverage activities, particularly as an engineer, I share more techniques on how to identify and make contributions with a big impact in this video: How to Identify and Make Contributions with a Big Impact.

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