Not everyone will do their work

If you have an obligation to do work, then please do it. Slacking off is one of the worst things you can do. It makes you look bad, and it makes me as your manager hate your guts.

You have to pick up the work they don’t do on top of your own.

If you choose to ignore the advice given above then I will have to pick up all the work you left undone to ensure everything gets done. As the person in charge I will get blamed for you not doing your work. And when your boss is stressed out, you are stressed out too.

The other people who work with you also suffer as a result

If you still manage not to do any work then everyone gets to suffer as a result. Like me, the one in charege, I would have to pick up your unfinished work, many others in a similar position to you will do the same. It’s unfair to have others do you work and expect to still be included in the team.

People are too sensitive

I understand people have feelings, but it isn’t fair to me or any other person being effected by a lazy coworker to constantly be doing the work of two, three, or sometimes even 4 people. If I ask you nicely to be sure to get something done on time, then get it done or at least let me know before the last minute that you can’t.

Promises are mostly empty.

You can promise all you like but actions speak louder than words. Your promises will be empty till you do something to prove to me you aren't the lazy person you have proven time and time again to be since the day we met.