Because people (including me) want something that looks nice without doing any work. Bootstrap met that; Tailwind looks nicer than the Bootstrap output, and is

Because people (including me) want something that looks nice without doing any work. Bootstrap met that; Tailwind looks nicer than the Bootstrap output, and is very handy to use to tweak everything. I'm ambivalent about the approach. So far the bigger problem is it moves too fast - with Bootstrap I can work on projects over a couple of years and nothing much changes. With Tailwind, it's new stuff every couple of months :)