Sleep patterns are that important?

Lately, i’ve been going to bed at different times. I find it’s harder to remember my dreams like this because usually i use auto suggestion to wake myself up. But since i go to bed at different times and everything, my internal clock is messed up. Is that how it is for everyone. Are sleep patterns that important?

I usually get to sleep around 1am, though sometimes it can take until 4am but I remember my dreams 80% of the time so I guess it doesn’t make that much difference. Maybe thats just for me though?

They are important. I read in a medical book that it would be healthier to have a consistent bed time. So, you should go to sleep at the same time as the day before and before that etc.