An industry "best practice" is to get feedback on every incident. Perhaps send a survey for every Y incidents but no more than X times in the previous Z time increment so you do not over survey. If necessary, exclude big honchos/senior people/touchy customers who don't want surveys.
We sometimes hear, "We don't want to waste our people's time filling out surveys…they should be doing "real work." A 1 question survey takes 10 seconds to fill out and it will make people feel like an important service provider is listening and that is part of building a self-perpetuating virtuous cycle for outstanding customer service.
The winner of the best law firm IT help desk in NYC from 2006 to 2010 surveys every incident. The very act of asking attorneys if the help desk has delivered great service makes the attorneys feel like the IT dept is willing to listen and improve. The willingness to listen and act is critical to improving customer satisfaction. Schulte Roth & Zabel is among the top 100 law firms in the world. The firm was awarded #1 Law Firm Help Desk in the USA in 2009 and 2008 from an independent survey performed by AmLaw Tech. From 2006 through 2010, SR&Z was ranked the #1 Law Firm Help Desk in New York City.
Whitepaper: "Learn How to Build a Virtuous Cycle for IT Technical Support"
We recommend that an external customer service organization perform surveys using the "Net Promoter" concept which is used by companies such as General Electric. This approach is to ask 1 or 2 questions with the theme, "Would you recommend our product or service to a close friend?"
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