A good example of where the term "partner carrier" gets besmirched would be the way a brokerage firm like La
xxxxde used to use it (maybe still do) ... they would market their services to customers as if they had some wheels of their own and would call in carriers that they have vetted to meet the customer's standards to help them out, when in truth about the only wheels La
xxxxde ever owned were like two Audi's and a Cadillac.
On the other hand, I use partner carriers to help me with my work (most are on this forum), and I am used as a partner carrier to help others with their work. The partner carriers I use are every bit as good a carrier as I am, and in turn I am every bit as good a carrier as the partners that use me.
In general, the term "double broker" can be pretty much applied to anyone getting in the middle of a transaction and offering zero value add, for a price.
Keep in mind that the vast majority of brokerages in North America are basement operations. These are the people that take a load from another broker, take out their 10%, and pass the load onto either an actual carrier or even another broker. They know nothing about the load, nor do they take, or accept, any responsibility for the load. They are a zero value add. Simply taking someone's hard earned money and offering absolutely nothing in return.
These are the people that everyone has problems with.
Don't be one of those people ... you wouldn't like the way most if us here would treat you

.