The Broken Zenefits Sales Team

Zenefits director of sales department believes that the company is currently  "overpaying" their sales people. This director, a position I actually volunteered for and was rejected doesn't seem to know what to do to fix this. My understanding is that they believe that they lack incentive to sell and should fire everyone.

This is of course a really bad expensive idea and won't fix anything either.
I used to train sales personnel for Cox, Century Link, Unthink and various other small startup and some not so small household brands.

Here is what I would suggest:

Develop a culture based on the current employees and managers, conduct surveys to find out what hobbies, interests, professional development, incentives, reductions in tasks, etc. are being currently sought after by the sales staff. 

Implement changes that reflect the most popular ideals that embrace and create value to the company's mission and vision. Company culture and improved customer service is a competitive factor that cannot be easily replicated and can help create "Blue Oceans" for any company. 

The changes in environment, expectations, limits, reductions, promotions, ideas, etc. will take time to implement but it will be much cheaper than firing and rehiring. It will also drive those who don't fit the culture to weed themselves out, or have weed each other out. Then as you replace with new hires, make referrals a strong focus, they are cheap but also help enforce that like mindedness in a team. The goal is to have a set of shared values that are so embedded in each employee on their own that matches company culture that you drive entrepreneurship with a sense of responsibility and ownership onto the what the company is about.
If you have clock punchers, workers that are motivated by the "have to" or "need to" you won't make a good sales force out of anyone no matter how much you pay or how many you fire or train. Culture is key. Drive value innovation among your team. 

I know you think is obvious but you would be surprised how much is not for some managers out there. 

Also, and just as important - TRAIN BETTER. 

Improving sales teams with the right words, rebuttals, sentence compositions, and linking, etc. will make sales so easy that they would have less of a reason to not complete sales quota for the month.  

I'm for hire, feel free to add me on linkedin.