People who like being up early assume that everyone is like them. Therefore they are busy carrying on a conversation with everyone in their vicinity immediately they are up. The other person may be mumbling not knowing how to stop this conversation from proceeding. Yet the early bird is oblivious of it.
On the other hand we have night owls who can work the whole night without falling asleep. While everyone is dozing off, they are all energetic. You would be forgiven to think that it’s the middle of the day. Many times they may make it so hard for others to sleep because of the noise they make.
Whatever category you fall into, it is not wrong. It’s a matter of preference. Do what works for you. Just remember to be considerate of the ones who are not like you. Agree to disagree on the preferred timings you have but do what needs to be done. If it’s a couple with different preferred times, sit down and chose a time where both of you are comfortable to bond.