As a programmer-turned-founder, this is something I have to remind myself all the time... it's often very hard to resist the urge to just keep coding and launching and throwing things at the wall until something sticks, because that's what I'm "good at" and it creates an illusion of productivity and "moving fast".

It seems like some people are commenting that the advice in the article is common sense, but I think when your mindset is to move fast, it can be easy to delude yourself into thinking you understand a problem when you're really just married to an idea but too scared to go out and discover whether it's actually solving something real or not.