I'll take a layman's crack... >Waking up at night because you have to pee? You may want to not drink large amounts of liquid before going to bed, altering you

I'll take a layman's crack... >Waking up at night because you have to pee? You may want to not drink large amounts of liquid before going to bed, altering your liquid consumption times/schedule could resolve this. >Waking up early because you got something on your mind (like work related problems that need solving) Stress is known to generally be bad for health and well-being, there are animals can outright die from too much stress. >Going to bed late because you addictively browse HN? Stick to a better schedule. >Jet lag after travels? Don't travel too much if you can help it. >Not taking an after lunch nap when I feel like it? This may have to do with an unhealthy diet >Needing to be wakened by an alarm? Personally I've noticed that after using an alarm for a month or so, I start to naturally wake up just before the alarm is set to go off. >Generally bad or not enough sleep? Definitely an issue, if you cannot find a solution on your own, you may want to see a specialist.