In essence the agent has the home in his pocket, meaning only he/she is the only one that know about it.
Both parties can win the agent gets a little more commission maybe or just the normal amount.
The seller gets his/her price.
This is neither good nor bad depending on the intentions. If the intention is to save some money for the seller then it is not necessarily a bad thing.
I personally believe that all homes should have a chance to get the highest and best offer and that takes exposure.
It is rare.
Especially today when putting it on the open market, the offered prices are way above comparable sold properties. The skies the limit. A pocket listing will restrict that free market pricing.
And the benefit is to the listing agent, not the seller, in most cases. My policy is not to represent both sides of a transaction so that my loyalty in the negotiation is clear. My policy is also not to complete a pocket listing unless specifically instructed by the seller, for example selling to someone they know.