When choosing an aws region which factors should you consider

Question

I have this question. So I setup my instance in Tokyo location. Later somehow it changed to Ohio location and I saw that my ec2 instance was not there. So later, I saw that after changing to tokyo again, I could see my instance. So I just had this question like what are the factors that should be taken into consideration when choosing aws region. I understand the speed matters so selecting locations close to customers makes most sense but are there any other factors?