Resistance
Microorganisms can only develop resistance to drugs directed against them if these drugs are directed against a mechanism or an enzyme system in the cell. In this case, the disruptive effects of the drug can be circumvented with the help of mutations or reserve enzyme systems that are only developed if necessary. Agents that generally target many systems of the cell cannot generate resistance.
For example hydroxymethylated formaldehyde many enzymes, proteins, DNA etc., malachite green coagulates the protoplasm, denatures proteins and enzymes. An attack on so many fronts at the same time cannot be fended off by the organism through adaptations.