Why would he message me at 4am in the morning?

Anonymous
I've been friends with this guy, on facebook, that i use to work with 2 years ago. when this guy decided to quit where we both worked before, i decided to message him on a social network and expressed my interest. but i never got a response so i left it alone. Just recently i got a message on Facebook at 4am and it was him asking me how i been. When i woke up i was surprised and decided to answer but never got a response. So my question is why would he message me at 4am and not even answer when i responded? ..what was the point>
Why would he message me at 4am in the morning?
3 Opinion