I think I have read of people mentioning this problem, however, cleaning
and re-tightening ground connections and a thorough test of the charging
system and battery would be a good idea.

Carl

Of course, 93 Legacy windows were no speed demons to start with, but;

As was already said, check the grounds, but since this is so universal,
it is what I have probably seen a hundred times.  The last owner just didn't
use these devices enough to keep them oxide free internally.

Check on most older cars with electric windows and you will find that
the windows used the most will work the best and fastest (unless they
burned out) and the windows used the least will get slower and slower
until they often just stop working altogether.  

It is beat to open and close your electric windows at least once a month
just to keep the parts moving and keep the oxide from building up inside
the motors.

If you are up to it, this can usually be fixed by just removing the window motor
(just?) cleaning it up by removing all oxide, scraping between the connectors,
greasing and reassembling.

But test first.  A lot of these windows use switches which are just contacts
on printed circuit boards so be sure you are getting juice to the motor and
therefore it is the motor. Also check the motor ground, if you still have juice
on the exit side of the motor (the "ground" when it is supposed to be working)
then you have a bad ground. Other ways exist of course like good old high
amperage continuity testers.  Use one with lots of juice because little electronics
testers can read enough continuity to make you think you have a ground
because it accepts so little flow as a connection, but then the big amps come
along to wind the window, and ,oooopps, there is not enough continuity !!.

The 'Ole Rep