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Ask 10 engineers what makes a switch feel good and you get 10 different answers: crisp, mushy, clicky, dead, premium. These terms are imprecise, but the behavior under each one boils down to a set of physical forces.

The feel of an electromechanical switch is the sum of several quantities that can be adjusted to produce different sensations: how hard you press, how far the button travels, how sharply the contact snaps over, and how the snappiness of the switch fades over time due to wear. Specify these parameters in the spec instead of leaving them to chance, and most complaints about the feel of the user interface turn into something you can settle during the design process.