Okay so this is a really bad crazy phenomenon that I have yet to crack. No joke, I turn my unwanted sketches into backyard bonfires. It smells really bad but it's cooler to watch than waiting for the trash man. Every round of fire papers, I always keep the ones I don't hate yet. This is a mere fraction of the paper I have used and the drawings I've drawn. Today, I have over 1500 of them lodged away in binders. These are all the sketches over the past 10 years that have survived my paper abuse. This is a fraction compared to the ones I've burned. Sometimes I wonder just how many drawings I've drawn so far, or what would happen if ?I kept them all.
I recommend scanning them into a digital album and throwing the physical paper away if you really want to keep everything. Keep just a few physicals, they add up. If you want to burn them, only burn a few at a time or they'll smell really bad (but they make cool flames) so do it in your backyard. It's fun n stuff.
Oh, also! After a few years, compile your old sketches into a progress video! =D