I know this isn't the typical 'problem', and it's not one I am complaining about. I just would like to have some more insight as to why this happened.

My computer started loading Morrowind very well without any lag. I have a very high end laptop, but it still experienced significant lag in heavily populated areas like Balmora Expansion. Now it has next to none. Also, the time it took to load the game was pretty decent (I have tons of large mods like Tamriel Rebuilt, MCA, etc so it took maybe 30-40 seconds just to reach the start menu from the desktop) and now it takes like 10 seconds max.

I do not use the laptop for anything other than Morrowind so I am not sure that I did anything or if the computer just recognized my overusage of Morrowind and started putting more energy into loading that?? I'm not really a computer guy so I don't know if it can do this or not. I am simply wondering what made it load so much more efficient, that way if it stops in the future maybe I can do something to make it better again.