So far I've made mistakes 3 (marginal niche), 8 (slowness in launching), 10 (having no specific user in mind) and 17 (fights between founders). They were painf

So far I've made mistakes 3 (marginal niche), 8 (slowness in launching), 10 (having no specific user in mind) and 17 (fights between founders). They were painful but instructive.