Also being a Volvo dealer master tech with about 20 yrs of pure Volvo dealer experience (more elsewhere), I can say that the problem areas you're describing would more likely occur if and when a "novice" tech gets your car and unfortunately that can and will happen anywhere you take your car, independants too. All places of business have to hire younger, less experienced "techs" and not all of them are good at what they've been hired to do. If they're then fired or quit, the next replacement guy is often not much better, sometimes even worse. The auto business is hardly "great" anywhere, dealer or indy and yes, I've worked for both. Some are simply better than others and it's all circumstancial.
Like the other guy, I also have customers who won't have anyone but me work on their cars (those customers have gotten to know me, talk to me, etc) and I make certain that their cars are always fixed right and they know it.
Most people don't know it but it's important to get to know your service writer (or "manager") and try talking to the tech who should have years of real Volvo experience. Don't let a kid work on your car if you think he'll fail to do the job correctly. You can request that you only want an experienced master tech work on your car IF you think that's necessary but if it's just an oil change, anyone "should be" able to do that right.