hyphenation - Noun + participle as adjective phrase

There's a construction in English that allows us to form a compound adjective from a noun and a past participle. Examples:

This is a volunteer-built home.

Our newspaper is student-run.

After the spill, beaches were littered with oil-soaked birds.

The way it works is pretty transparent: [subject noun] + [verb participle] modifies [object noun]. However, it occurred to me that we can't just plug any subject, object, and verb into this formula. Some sound completely wrong/impossible:

*This is a cat-used litterbox.

*I wanted to buy my daughter the most child-wanted toy.

*I was uncomfortable lying down in the hobo-slept bed.

Thinking about it, I couldn't come up with a clear rule that determines why some words can fit this construction acceptably and some can't. Why is that?

Answer

First, hobo-slept doesn’t work because (in most dialects) you can’t say “I slept the bed”. But I think there are a couple of different things at work in your other examples. In the first set, the noun part of the compound modifier is pretty much required in order to make sense of the sentence:

This is a built home. (Built by whom?)

Our newspaper is run. (Run by whom?)

The beaches were littered with soaked birds. (Soaked with what? Water?)

Whereas in your other examples, the subject can be assumed:

This is a used litterbox. (Used by a cat.)

This is the most wanted toy. (Wanted by anyone.)

But for those cases where there is a common assumed subject, you can change it explicitly:

This isn’t just a used litterbox—it’s a human-used one!

As far as I can think of, that’s only done for effect. It’s no wonder, then, that child-wanted sounds a bit odd when you aren’t deliberately contrasting it with, for instance, another kind of person doing the wanting. I would say the general rule is this: if the subject part is not required, then it can only be included for emphasis.