The answer to this question depends on the type of programming you do. 1) Working as a part of an enterprise team on a big lump of TypeScript and React? Then

The answer to this question depends on the type of programming you do. 1) Working as a part of an enterprise team on a big lump of TypeScript and React? Then you probably don't write tests before you code because a) TypeScript catches all the bugs amirite? and b) Your test runner is probably too hairy to craft any tests by hand, and c) You are probably autogenerating tests _after_ writing your code, based on the output of the code you just wrote, code which may or may not actually work as intended. 2) Working on an npm module that has pretty tightly defined behaviour and the potential to attract random updates from random people? Then you _need_ to write at least some tests ahead of time because it is the only practical way to enshrine that module's behavior. You need a way to ensure that small changes/improvements under the hood don't alter the module's API. This means less work for you in the long run, and since you are a sensible human being and therefore lazy, you will write the tests before you write the code.