Many of the significant projects in our life take around 3-5 years to complete.
E.g. Writing a book, starting a family, creating a company, learning a new skill/instrument, or completing a degree.
When you pair this with the insight that the average lifespan is approx. 80 years, it can provide a wake up call about the finiteness of our time and the importance of choosing our projects wisely.
In my case, I’m writing this at the age of 32.
And if I subtract my age from 80, I get 48 years.
Then, if I divide that by 5 (the approx. number of years it’ll take to complete a significant project), I get 9.
This means that — if I’m lucky — I’ll get to work on only 9 more meaningful long term projects in my lifetime.
When I made this calculation, it dawned on me that:
(1.) Life is way too short to waste time on projects we’re not fully aligned with,
(2.) We need to be careful about what we commit to, and:
(3.) We need to carve out time and begin taking action on the projects that matter most — because no one else will do this for us.
If you’d like to avoid wasting your time by going down wrong paths, one of the most effective tools for choosing the optimal projects to focus on is the “Happy, Smart, & Useful” framework developed by Derek Sivers.

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According to Sivers, for a project to be sustainable, it has to pass three criteria:
(1.) Happy, in the sense that it should bring you joy and energy as you work towards achieving it;
(2.) Smart, in that it should be good for you in the long run, and;
(3.) Useful in that it should be valuable to others.
When a long term plan doesn’t work, it’s usually because we’ve neglected one of these elements.
To illustrate this, let’s look at three examples.
Firstly, happy and smart (but not useful) plans are often created by those in the “lifestyle design” industry. They prioritise creating passive income, so they can sit on a beach and sip margaritas, while the money flows in effortlessly. People who only take happy and smart into the equation forget that human beings are an intensely social species. We’re hardwired to connect and serve, with research showing that we receive a myriad of unseen emotional benefits when we help others. So we’d be wise to acknowledge this and find ways to serve others through our work.
Secondly, a happy and useful (but not smart) project might involve a coach who invests heavily in training to become the best coach she can be. Then, after qualifying, spends all of her time helping her friends at no cost. Although it makes her happy and is useful to others, it’s not smart (i.e., good for her) in the long run because she will soon find herself broke.
Thirdly, a long term plan that is smart and useful which neglects happiness is also not a sustainable strategy.
As Jack Kornfield puts it:
“If your compassion does not include yourself, it is incomplete.”
Those who are “other-focused” have a tendency to fall into this category. An example might be an entrepreneur who wants to help others improve their lives. What he really loves doing though is organising events, coaching, and writing. But he neglects this because he thinks that to make a bigger impact in the world, he should start a nonprofit. So he starts the nonprofit without considering what the day-to-day of this actually involves. Now, most of his time is spent applying for funding, managing a team, and checking the work of others – none of which he enjoys or finds intrinsically motivating.
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So, when thinking about the project you want to pursue, ask:
1.) Will the pursuit of this make me happy?
2.) Will it be good for me in the long run?
3.) Is it useful to others?