The hose on the supply side to the valve is the hose I am referring to that is pressurized “full-time”. Hoses on the output side of valves obviously would only be pressured during watering.
I setup a system for a family member in southern utah where burying pipes would be extremely difficult. I did bury boxes that contained standard irrigation valves with fittings converting to hoses. After just a couple years the hoses, hose bibb (o-rings), and sprinkler heads on the system were failing. I figured it was a combination of constant pressure (in the short hoses supplying valves) and the HEAT.
Some type of machine was rented for trenching and it resulted in a failure. That lead to the decision to use a hose system. Some of the hoses were buried, but mostly they were surface or close to surface and susceptible to the sun’s rays.