Do you want to play fast but when you try your playing sounds sloppy?
Something that might be causing your playing to sound sloppy is lifting the fingers of your fretting hand too high while playing.
This can also inhibit speed.
If you lift the fingers of your fretting hand up quite high while playing, it makes it harder to play notes with more accuracy.
If your fingers are lifting up quite high from the strings it also makes it harder to play fast.
Watch a drummer playing a drum roll – their sticks and hands stay close to the snare.
It would be impossible to match the speed they can achieve with that technique if they were lifting their sticks above their head.
It would also make it much harder to play accurately.