Unfortunately that's not enough to guarantee success. Even the most well run company can still fail to find product market fit, just be at the wrong time, or just get screwed over by external factors or even other internal factors. Conversely, a poorly run company with a toxic culture can succeed despite problems a rank and file employee might see.

If you've joined unicorn X pre-IPO, you've hopefully got a decent amount of pre-IPO options, at which point might I suggest diversifying in case the market doesn't share your confidence in the company.