How often you clean and how deeply really depends on your number of birds, size of coop, and general environment. What works in one set up; won't necessarily work in another. What doesn't work for you doesn't mean it won't for someone else.
For example, many extol the virtues of sand. However, in my clay soil, sand plus clay makes for cement. In my wet environment, sand plus constant drizzle makes for stagnate stink, until it dries enough for cement. All my chicken friends in my area hate sand too, but there are many in other places who use sand very successfully in their coops because of their environmental set up.
I clean out my coops about once a week, sometimes every other week. I have about 7 to 8 birds per coop in about 4 by 6 foot or 5 by 8 foot coops. So the birds have plenty of room, which means I have less build up quickly.
I dump the pine shavings from the coop onto the run dirt, which over time has deep littered with my clay soil into beautiful, non stinky loam. I don't use DE as that prevents the good bacteria from doing its job with the deep litter. The deep litter must be in direct contact with soil to promote the good bacteria breaking stuff down.
Every spring, since I have a bad back, I call up my gardening friends who gleefully bring buckets and shovels to scoop up my black gold for their gardens. (Yes, I have a bit of Tom Sawyer in me).
About once a year, maybe every other year, I take hydrogen peroxide in warm water and let that slosh over my coop floors. It lifts caked on dirt and crud as well as disinfects. I then can easily slosh it clean.
But I don't get heavy build up in my coops because I use empty feed bags cut up for coop floor liners. That really helps keep the floor clean. I just lift the liners, roll a bit like a burrito, then dump the whole lot onto the runs. I change out liners as they become soiled.
Pine shavings, in my environment, bind with the fecal material nicely (the carbon with the ammonia), and beautifully hold down the smell. If I notice any smell at all, or see some damp settling in (remember I'm in Oregon with nearly constant drizzle from September through June), I add fresh pine shavings to the runs.
This works very well for me and my soil and my size of flock and coop/runs.
Each owner must discover what works best for them.
LofMc