this happens to me all the time...
what happens is the fluid supply line gets clogged for whatever reason- probably due to lack of use during the summer. then when winter comes along when i pull the lever to squirt windshield wiper fluid the pump tries to move the fluid but it can't cuz of the clog.
out of frustration i keep trying it repeatedly, which eventually burns out that tiny motor that turns the hydraulic pump. and, then has to be replaced.
i've had it repaired about 3 or 4 times now- now on my 10th year of ownership. it's about a $15 part & my shop charges me about $10 to do the install, so $25. when they do the install, they also flush/ clean out the fluid supply line so it doesn't clog again... well, until the next time i guess.
the best thing to do is to periodically use the windshield wiper fluid- regardless if u need to or not. it keeps the line clean and prevents clogging. only in sunny southern california, i can never remember to do it!
hope this helps.