As said up thread, many of the former mom and pop motels have been bought by the big chains. So it helps to look at a photo of the property - if it looks like the standard chain motels, it is. Best Western is a good example where there are a chain style properties and any number of semi-independent properties each with their own architecture, room layout, and style.

That being said, for work, on someone else's dime, I usually just stay at a convenient chain with preference for one from which I collect points or have status to get an upgraded room. In Europe of course it almost always non-chain hotels as that is what is available. I always have a bit of doubt in one, but then I've always been happy.

For family travel, we tend to go with non-chain motels, with emphasis on relatively low cost. We are outdoors people and generally don't care too much where we sleep as long as it is quiet and has fridge and microwave. We've done vrbo and were happy with that, but the motel search is so much easier now with sites like tripadvisor. You have to sift through the reviews but it can be well worth it. Just a few weeks ago we stayed in a real nice 6 unit motel near Joshua Tree, in a room with a really nice kitchen, that I never would have even found much less chosen without the chance to read reviews.

Lately I have also started using extended stay hotels for both work and leisure. I prefer not to eat out, as I'm working on weight control, and it's very helpful to know just how a kitchen will be stocked and how big a fridge you'll get.

I've also had some really nice family stays in higher grade hotels - Andaz near Liverpool St Station comes to mine as heavenly - using those points from the boring chains.
In other words... a mix and a bunch of work to go off-chain, but often worth it.