Interestingly, I thought that too. So when I became a manager, I put all of my corporate political clout into defending devs against ever having a hard schedule or pressure to estimate without enough info. Amazingly, it took more than a year to break the cycle: bad code, and claims of not enough time. It's like a reflex for many devs.

I constantly beat the drum for quality and the practices to enable it. but i agree with others, just the manager's actions are not the reason. As a dev I didn't let managers bully me into bad code, and as a manager just giving permission to do things right wasn't enough.