This. Each to their own. Some DJs have the headphones on with tracks in different ears (split cue), I do the “traditional” method of the track that is being mixed in playing in 1 ear (my left, as my right has blown the bass out so I need serious volume to hear anything in that one!!).
I tend to only change over when the track is fully in and the old one is out, as you still need to listen in for subtle adjustments. When I was a kid and wanted to mix when my parents were asleep, I learnt to mix solely in the headphones, which is also helpful when the monitors in clubs is ■■■■, or the echo is bouncing around really unhelpfully!
As @PKtheDJ has said, whatever works for you will be respected, no one judges you (don’t wear Beats headphones though, or then we would judge you )