When you invest time in work that has nothing to do with the base expectations of your current task that could benefit your experience, task at hand or overarching project it could be considered growth work. This growth work has the potential to expand your knowledge and or craft by learning new concepts, tricks or other things, which is often compounding over time.
Just be sure that it does not interfere with base work.
Make sure you also don’t fall into the traps of Premature optimization which is procrastination, Over engineering, which is bad for a project or increase the cognitive complexity too much.
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Assume there’s a reasonable amount of work you need to do to fulfill the base expectations for your job (i.e. your Normal Work) and then there’s a little time left over. (I know some may argue this “left-over time” thing, but just go with me). In this remainder time you have a choice: you can do More, Extra, or Nothing
— Quote from Always do Extra - Ben Northrop highlights
Extra is finishing those two screens, but then researching a new library for form validation that might reduce the boilerplate code. Or it’s learning ways to protect against common security vulnerabilities from data entry. These little off-ramps from the main highway of Normal Work could be dead-ends and not have any practical value to the project. But they might also be important contributions. And that’s the thing with Extra. While the tangible value to the project is uncertain (it could be nothing this time or it could be something), the value to you is real.
— Quote from Always do Extra - Ben Northrop highlights