I see that happen quite often.
How do hearing people learn to talk? by hearing other people talk right? So why would you say that some deaf people are lazy because they cannot hear? It's difficult for them to speak when they can't even hear themselves producing sounds correctly. It takes a lot of time, effort and determination. It may be harder on some deaf people who cannot get their tongues in the right place, it doesn't mean they are lazy, it can be very frustrated though. 
