Here's why:
* Asses don't wag their ears. Donkeys (asses) have ears that can swivel and move independently, but they don't wag them like dogs do their tails.
* The phrase doesn't have a clear meaning. It's unclear what the phrase is trying to convey, even if we were to assume the ears are wagging.
Possible Misinterpretations:
* "All asses are the same": This is a derogatory phrase that means everyone is stupid or alike. However, the "ears" part doesn't make sense.
* A misheard phrase: It's possible the phrase was misunderstood or misremembered from another saying.
If you heard this phrase in a specific context, please provide more information so I can better understand what it might mean.