This is the classic naive perspective. To a serious extent, experience tells you what to build and when. The actual building is quite often better to farm out to someone who can be bothered to trawl through familiarity with the latest 5-minute javascript framework. That is why successful founders tend to be middle aged[0]: they know when not to waste resources, and to use the right tool for the job. That tool might be you.

Furious activity is no substitute for understanding. - H. H. Williams

... via https://github.com/globalcitizen/taoup

[0] https://theconversation.com/most-successful-entrepreneurs-ar...