The main reason brake hoses do not release after pedal application is they are constricted from swelling inside. When one applies the brake ,the Master has a great enough pressure force to flow thru the constriction, but when released , the only force to return/release the calipers is Residual pressure ..much less than pedal pressure...resulting in a hanging brake pad.
An easy test for this condition is to jack each wheel , apply the pedal force , and then hand turn that wheel..if wheel is locked [or excessive drag]. open bleeder ..if the wheel then frees , you have a bad hose. if it doesn't , you have stuck caliper.

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A Dalton