Why does the transmission fluid dipstick present so much difficulty to put back in?

It is unnerving sometimes that the dipstick for the transmission fluid resists being reinserted after it slid out so easily.

The trick lies in the fact that usually the tube that holds the dipstick has a bend, not a huge bend, but a bend of 5 or 10 degrees.

The dipstick is a flat piece of metal, which means it bends easily in one direction and not at all in the perpendicular direction.

One must reinsert the dipstick so it is oriented so that the direction of bend of the dipstick matches the direction of bend of the tube. Being even a small amount off puts force on the dipstick to bend in the wrong direction and it just won't do it.

People develop their own technique for this and the technique varies with the car since there are slightly more awkward dipsticks and some easier to deal with. In some cases, people just push and pull and turn and push until they feel the orientation improving and gradually find the orientation to get it in. Other people carefully look at the tube and look at the stick and slowly insert it using the visual queues.

It is something that has been part of the design of almost all cars and trucks for decades and decades and decades.