Tbh I am amazed that we ever remember anything at all, what with having to convert what is in the outside world into a neural representation that can be stored over time without being damaged.
Seriously though, if you think of the steps involved in order to keep a memory in terms of neurobiology you would be amazed too when you have to factor in encoding and cell death/regeneration. At least you can see why artifacts in memory happen as described by Bartlett; because our memory is actually limited.
Think of it as redrawing a picture from real life using only the tools of an art program (eg Paint). You only have a limited range of tools available which can be used to encapsulate the reality of the picture. Of course you expect errors to appear when trying to match up, and depending on your tools some aspects may be overlooked, simplified etc etc. For example, if you want to draw smoke you can use the spraycan tool which may reproduce the idea of smoke, but fail to replicate it entirely.
This brings me to my next point: memory also works based on other principles such as importance. Important things tend to be remembered better than non important because of how limited memory is at storing things. This has been shown in countless studies and has been shown to produce countless biases (attentional blindness in the gorilla experiment, focusing on emotional stimuli such as weapons).
And finally we also find that previous memories affect later ones in a similar manner, which biases our memories. This is because we have schemas of our world around us which help us store and retrieve memories. When the outside reality is incompatible, this often resorts in errors such as false memories or omissions of important things, hence forgetting.
I hope that answered your question, despite taking a different (and weird) route to answering it.