= Explain how to make money with the lesson
People will be more interested if they see how the stuff they are learning is useful.
Useful 99% of the time means you can make <money> with it.
Achieving <novel results> for <science>, or charitable goals (e.g. creating novel tutorials) are also equaly valid. Note that those also imply you being able to make a living out of something, just that you will be getting donations and not become infinitey rich. and that is fine.
Projects don't need of course to reach the level of <novel result>. But they must at least aim at moving towards that.
This is one of the greatest challenges of education, since a huge part of the useful information is locked under <military-industrial complex>[enterprise or military secrecy], or even <the missing link between basic and advanced>[open academic incomprehensibility], making it nearly to impossible for the front-line educators to actually find and teach real use cases.