As a sales guy myself by training and tech sales by profession that sounds very much like there are some very fucked incentive structures at play that need to be addressed. If they're only monitored on number of deals closed then you get shit like that trying to meet targets and get the bonus that is extremely standard in the sales profession and account for a large share of the yearly salary. If they're measured on profitability then you wouldn't see that, they'd drop stingy clients themselves for wasting their time. Another solution I've seen is having a larger bonus for customer satisfaction and renewals / growing the contract but that only really works out if your sales also doubles as account managers.