The U.S. Postal Service undervalues and underappreciates both its Carrier and its Clerk workforce. Yes, both are fairly compensated financially. But both are treated as "burdens" to management and not as the backbone of the service that they are.
Pay and benefits
Unfair and downright nasty treatment by management.
The supervisors were really nice and helpful. Even part time employees were given appreciation often. Everyone got along. A lot of manual work and not for the faint of heart, but with good work ethic you'll have the time of your life