Do you trust machines??

This morning i went to xx bank to deposit cash, using the cash deposit machine. There's 2 guys in front of me. I noticed that the first guy after finished depositing the cash, he straight away go to atm and check. I think he's checking whether his money has been deposited or not cos i didn't see him withdrawing any cash. then the 2nd guy did the same thing also..

does this shows that the machine is not trust worthy?

how many of you did the same thing? after deposit cash, then check balance at atm?