Everyone loves a “can do” attitude. “Yes, we can!” has become — even when stripped of any political connotations — the rallying call of an entire generation, empowered, driven, and enthusiastic. For a young startup, this type of optimism is a prerequisite. Pessimists would probably never embark on a dangerous journey into uncharted waters, let alone survive the trials and tribulations that are an integral part of bringing a new product to market. But as startups grow, rampant positivity won’t always serve you well.