Do you wake up in the morning and immediately forget what you were dreaming about? The ability to recall dreams varies widely among people, and can vary over time for each person. There's a lot we don't know about dreams, or even sleep itself, but research into the difference between dream recallers and dream forgetters has unearthed a few factors that may determine the difference.
4. AMOUNT OF SLEEP
The amount of sleep one gets on average is one of the most important factors related to dream recall. People dream every 90 minutes during the REM (rapid eye movement) sleep cycle. However, those REM periods get longer throughout the night, meaning that you’re doing the most dreaming toward the morning—generally right before you wake up. If you only sleep four hours instead of eight, you’re only getting about 20 percent of your dream time. For this reason, some people report remembering more of their dreams on the weekend, when they have the chance to catch up on sleep.
That explains my experience, as I haven't had eight uninterrupted hours of sleep in decades. There are five other differences that might determine whether you recall dreams or not at Mental Floss.