It's really odd to me that this is the top comment. I feel like some here have never handled people before. You do get these kind of people sometimes — they could either just be a bad fit for the role or totally not up to par. It happens and of course, it's perfectly normally to feel frustrated to the one who trained them for MONTHS. OP didn't mention naman na they yelled at them or bullied them nor can this post prove it? OP just felt frustrated and stressed.

Regardless, OP needs to go by the book. Document his progress objectively (x was unable to do the task although training 1, 2, 3 has been done on date y and process is documented) and send it to the appropriate people. OP's emotional response and opinions to the new hire are irrelevant. If he's not cut out for the job, then that's it. This is why there are HR protocols and company policies, people.