Antibiotic resistance is a common concern, but not so much resistance to detergents, such as hand soap. Why is this? Is it simply easier for microbes to evolve mechanisms to deal with relatively small concentrations of drugs, relative to often much higher concentrations of detergents? Or is it simply that many human pathogens aren’t transmitted via skin or indoor surfaces, and so their resistance to detergents isn’t a major factor in their transmission? Or something else?
Firstly, detergents are not bactericid, they are supposed to remove the crude dirt. That’s way bacteria don’t need any resistance to soap.
Contrary, if the higher concentrations were more deadly, the bacteria would be pushed even harder to evolve some resistance.
There are a great many materials that bacteria cannot evolve a resistance to. Anything that has a gross effect is immune to resistance. For example : bacteria cannot evolve resistance to bleaches or to caustic materials since these chemically disintegrate the cell membrane. Nothing subtle there to get around.
Things like antibiotics can be different, since a change in an enzyme or similar may provide a metabolic pathway around that which is disrupted by the antibiotic. Or else a new enzyme that destroys the antibiotic.
But quite a lot of chemicals are too unsubtle in their action for such mechanisms of resistance to work. I suspect detergents are among them, since they dissolve fatty materials. Such fatty materials are part of the cell membrane. Destroy the cell membrane and the bacteria is dead and gone.