A motor, Delta bandsaw, has a name plate with the following information:
120/240 volts
1.5/2.0 hp
12.8/8.6 amps
For 120 volt use it appears that a 20amp circuit is required.
In reality the motor is
120/240 volts
2.0/2.0 hp
17.2/8.6 amps
Now, a 25amp circuit is required.
What prevents manufacturers of other equipment from "derating" their products to avoid the 80% or 50% rule.
I can see manufacturers selling a suite of kitchen appliances - dishwasher, disposal, refrigerator, and freezer, that all fit on one 20amp circuit.