key thing i have found in the level of dream recall has been about the level of protein in the diet and the proximity of eating to sleeping, and other things play a role, but it's mostly about how much tyrosine and phenylalanine is in your blood, whether you are likely to wake up

needing to pee - maybe more likely to remember dreams

loud noises right as you are in REM - you will remember the dreams, but maybe whatever made the noise will wipe your memory fast