Too much WIPS :(

I always been wondering why my coloring style or lineart style has not improved in the past 2 years but my artstyle has improved...And then I look threw my folder and I see that I've drawn like aloooot of artwork in the past 2 years its not like I haven't been drawing but most of it is like sketches.. And then I realized that the reason my coloring or linearting style has not changed or improved but my artstyle has was because I was drawing only sketches and never got to actually finishing an art piece...And I have countless of un finished WIPS. Mosty all sketches and I'm like well... I'm never gunna get better in the coloring and linearting stage if I don't get to it..LOL..But I just cant stop drawing new things in sketches...and then I get too lazy to do the coloring or linearting..Or get distracted by a new sketch or desire to want to sketch a new piece of artwork..But it keeps piling up and piling up..And I tried to make myself stop sketching and FINISH all my pieces but oh man that was useless lol... Mostly cause my older artwork doesn't look as good as my newer so I feel like.. 'Why should I finish this?' LOL...It's so stressful Idk what to do. I could simply contiune doing what I do which is sketching and everynow and then I DO Finish something but its only like one piece...of artwork lol..BUT Then I'll just improve in my art style and not in my coloring or linearting and I want to be good at that too...AHHH It's so frustrating! I think thisis all because the desk i work on is really low and hurts my back so when i spent over 6 hours on a drawing my back starts to ache like heck and then I have to stop and cant draw till 2 or 3 days later..Maybe it's not my procrastination...Idk...Man LOL. Idk. Anyone have any solutions?

LOL Man most of my sai files of my drawings have like 5 or 6 different sketches in them...FFFF...LOL. I sketch way too muchhh.... ;___;

I'm the polar opposite. I have to spend forever on a single pic. I'll get lost in the details and keep trying to make every little thing perfect. And once I'm done, all I see are the areas that I want to make better. It seems like my rate for completion is about a piece of art a month. It also doesn't help that I'm super lazy. It's like regular lazy but you get to wear a cape.