Most likely a bad or failing window motor. When they are about shot they cut out and then work after a few minutes. There is a heat resister in motor, that cuts out when it gets to warm to stop from burning out the motor. After a little bit it cools down and will work for a few more seconds. I would replace the motor, which is a pain, and involves drilling 3 rivets out and 3 small holes inside your inner door panel, while you have the interior panel off the door, use silicone lube on the window tracks so it'll glide better. Theres videos all over youtube about doing it. The motors run $25-60 depending on brand and quality. Also check if your window has some in and out play, indicating worn out roller wheels, or the window slides that are covered in a velvet material(one in front and back on top) can wear thin making the window loose.