With webapps being more and more common in business, it has not gone unnoticed by customers that you can roll out fixes and upgrades fast.
I think there is increasing pressure to answer "will be done ASAP" to every request, especially to bug reports. For programmers, ASAP work sucks. It takes self-control out of the work. In the long run, putting out fires chronically is unefficient and unprofessional, but in the short term, the client is more happy with your answer.
How do you deal with ASAP requests? I mean, do you have SLAs to define accepted response times or do you negotiate case-by-case? If you have SLAs are they adhered to?
In our case, we have SLAs with some customers but they don't matter much. SLA is more like an excuse if you can't do things immediately. Usually the severity of the issue matters, but some customers are better negotiators and override nicer customers who otherwise would have more urgent needs.
Of course, avoiding ASAP work with quality control would be the ideal approach. But the truth is, many SaaS offerings are practically tested with customers, in production.