What made me a good designer wasn’t my years of coding, but my profound understanding of the invisible demons programmers wrestle with. If a designer is skilled at their craft, knowledge of these development demons is what makes them successful at their job.
This is one of the reasons I encourage entrepreneurs to bootstrap instead of taking outside money. On day one, a bootstrapped company sets out to make money. They have no choice, really. On day one a funded company sets out to spend money. They hire, they buy, they invest, they spend. Making money isn’t important yet. They practice spending, not making.