Pre-measured cleaning tablets dissolve into the bath at a fixed concentration. The reason to use them is consistency: a tablet delivers the same dose every time, where liquid concentrate measured by eye at the start of a shift does not.
Concentration matters more than most operators expect. Too weak and cleaning slows down and results drift through the day; too strong wastes chemistry and, with some materials, risks attacking the surface. Because the dose is fixed, tablets remove that variable entirely — which is useful when several people share a machine, or when cleaning is part of a documented process.
They also remove the handling side of liquid concentrate: no drums to store, no decanting, no measuring. For benchtop machines and smaller tanks that convenience is often the deciding factor.