Property Managers - Why do they always Overpromise and Underdeliver?

[Mat Lewczenko]

I hear this ALOT...
"I had a great PM company, paid them $X but they are gone, had to fire them. They were great in the beginning and then..."

What makes them great at the beginning?
What are the biggest let downs?

I ask because my partner and I are putting together a business plan to start managing other investor's properties as well.

What do you all think is the best Value Proposition that we could offer that the current management pool is lacking in.

Very interested to hear everyone's perspective.