Reminiscing about times when practicing Aikido was with an actual living partner and included physical contact, made me categorize types of bad Ukes as I experienced it.
The Brute - The aggressive uke who will hold as tightly as he can, or strike as forcefully as he can, disregarding his partner's situation. More than just being intimidating to a smaller or less experienced nage, it’s totally insensitive and irresponsible.
The Pacifist - This uke will not give his partner an honest attack to work with, for fear of injuring others.
The Dishonest - The uke that falls down for their partner in response to a weakly-applied technique. They offer no real resistance and they just let themselves be thrown. When working with a new student this is a good type of uke to be, but when working with a more experienced nage it can be perceived as condescending or as a lack of attention.
The Blocker - Because they can?...