When a junior colleague tells me a paper has been rejected, I respond that it's good they're getting the rejections out of the way so they can get to the publications. I'm sure they think I'm an idiot, but I'm completely serious. You can't learn what it takes to get a good publication until you've had some rejections. It's all part of the learning process.

I think that's the real message here. Be prolific in activities that can teach you something useful. Just pumping out a load of garbage won't help you any more than practicing bad shooting form will make you a good basketball player.