What causes the gear shift to stick in an Audi 80?

I've noticed that my Audi 80's gear shift sometimes gets stuck when I try to change gears. It doesn't happen all the time, but when it does, it's really hard to move it. Can anyone help me figure out what's causing this issue?

The most common cause of a stuck gear shift in an Audi 80 is a problem with the shift cable. It can become corroded or worn over time, which can make it difficult to move the gear shift smoothly.

Another possible cause is an issue with the shift solenoid. This is a small device that controls the movement of the gear shift. If it becomes damaged or malfunctions, it can cause the gear shift to stick.

It could also be a problem with the gearshift lever or linkage. If these parts are damaged or misaligned, it can affect the movement of the gear shift and cause it to stick.