Every company is different and not every company has the same sales management needs. As the Inc. article below points out, not everyone needs a sales manager in the traditional sense.
http://www.inc.com/articles/201106/what-to-look-for-in-a-star-salesperson.html
Occasionally, we find the exceptional sales team that functions effectively without a traditional sales manager.
As the article points out, experienced sales teams can forego some of the sales management activities because of their efficiency and proven performance level.
If your team meets these requirements, you may want to consider a management-less team. Be advised, this is a short cut methodology. With all short cuts, time is saved while other aspects may be sacrificed. Don’t delude yourself into thinking a management-less team will function with exactly the same efficiency as one lead by a pro sales manager.
That said, if you are lucky enough to have the right team, take advantage of the cost savings a manger-less team can provide.