Crappy managers stress delivery over quality, and then engineers pay for it when they're oncall. The manager doesn't care how much their team gets paged because

Crappy managers stress delivery over quality, and then engineers pay for it when they're oncall. The manager doesn't care how much their team gets paged because they'll be sound asleep while their engineer bangs their head against the wall at 2am, and the manager gets their pat on the head for delivering more projects.