I have heard once that we forget more than we remember. There is as most know a specific field within psychology devoted to memory offering why we forget and how we can better remember. A short search and jump to an article about forgetting would be my recommendation. Consider memory type - sensory, short or working, and long term. Those have subdivisions too.
Trace decay - focuses that memory can only hold info for 15 - 30 seconds
Displacement - new information pushes out old information (Can occur in a few moments)
Interference - 1) Proactive means cannot learn something new because of something old 2) Retroactive or forget something previously learned by something new learned
Lack of consolidation - biological causes, i.e., amnesia, brain chemical balance, neurons & etc.
Retrieval failure - stored in long term memory & cannot be accessed
Context (External) Cues - for instance a house on a corner is blue and that is where you turn right on the road
State (Internal) dependent cues - similar circumstances to when first experienced / remembered triggers memory recall
A reminder is sometimes it is not the inability to recall itself. It is the confusion of all the memories that are familiar trying to be recalled. If you have a million lists in your head and someone says check your list you just wrote it down you may recall the lists, yet which one.
Having memory recall challenges myself I might respond to that with "which list". With humor I write stuff down on a 3x5 spiral pad. If I don't remember to bring the pad with me, then I simply do not recall what was written down. What is worse is if I don't wear a shirt with a pocket in it I will forget the spiral pad.
For me living alone I used those theories to discover which forgetting type affects me most. For instance if I am told more than 2 or 3 things to do I will forget the first thing. That is just the way it is. It will not change. So, I must write it down or if a list is given to me that helps. My old bosses could not accept that of me.
I finally made stations for myself in the home. I have a leaving the home station, I have a stuff to do at the desk station, I have a stuff to do at home station, and etc. I will most definitely remember to check those stations, however I can attest the likely hood of remembering what is at those stations is much less. I am sure my home looks weird inside because of that. But, it is patterned how I remember, not how someone else does.