Maybe all the other native English speakers already know this, or would never have given it a second thought, but I thought about this today.
Let’s call on our friend, the German language, to make the words reveal a little more.
What’s the German for “develop?” It’s “entwickeln.” Entwickeln consists of two parts, “ent” and “wickeln“. “Ent” generally means something like an “un-” prefix in English or otherwise conveys the sense of removal. “wickeln” means “to wrap” or “to wind” or “to roll (up)”.
OK, here’s where the light bulb started to shine for me: when you take film in to be developed, they have to unroll it. Ding ding ding!
So…when you “develop”, you’re taking something out of its “velop”. When you’re done with it, you put it back “en.” Right?