In fact, four out of 10 HR managers say they derive valuable information from them. Unfortunately, many techies blow that potential opportunity by burning their bridges. Remember that 'farewell' isn't necessarily forever. Bosses and co-workers leave. You could end up meeting again.
Exit interviews are a time when emotions can run high on both sides.
It's important that everyone remember that this is a professional exchange and not a time for the techie to take shots at his former boss. This is a time to be honest, but not blunt, and for each person to respect the decision of the other. Go in with an open mind about staying. The exit interview might offer you a negotiating opportunity. Some employees get good counteroffers in the process.