Why OD of honed tubes sometime also be Polished?

1. For telescopic cylinder tube use. 

Some honed tubes are used for telescopic cylinder, then the OD maybe need polished and then chrome plated. Because there are still other honed tubes out of this honed tubes.

2. For better painting 。

Polish OD of honed tubes could make painting better adhere to the OD. It will make painting looks smooth and beautiful.