I've always felt that to hire an editor to work with me on a poetry manuscript would be something like admitting defeat. So the experience of working with an editor was illuminating. It wasn't humbling in the way I thought, rather it made me want to expand my horizons, take more workshops, read more widely, work harder, and take more time with the publishing process. It also gave me better ideas about the marketing of poetry manuscripts, the competitive environment and how to navigate it, and the processes of contests and submissions in general.
As a contributing editor at Umbrella, I have had a look behind the scenes in editing a journal. But I would say that Umbrella, as an independent magazine, is an elegant and economical operation under Kate Bernadette Benedict's guidance. To steer through a university-affiliated magazine, you must often get past an army of first readers, many of whom might be just starting out in poetry. You must make it through a sometimes not impartial process -- though this is controversial, and many journals are moving to ensure that their blind judging of contests is squeaky clean -- and you must be simply lucky, given the numbers.