Do what you say and do it right

Problem 1:
I take my car in today for an oil change and tire rotation. Several hours later I get a call that the car is ready. I pay and get my keys and go to my car. As I pull out of the parking spot I hear my passenger side rear tire banging against the wheel drum. I immediately stop and notice they never tightened the lug nuts on the wheel and one is missing.

Question 1: Didn't he hear that when he pulled the car out of the bay?
Question 2: What else did he forget to do?

So I carefully drove the car back to the bay and they re-tightened all the tires. I have to wait until Monday for the missing lug nut.

Problem 2:
My partner hires a roofing company to replace his roof. The roof was damaged during the 2005 hurricane season. The roof was started several months ago. To make a long story short. Half his roof is done and now needs to be pulled off and re-done from scratch.

Conclusion:
I could continue with these stories all night. How is it possible that quality and customer service does not exist anymore? Everytime I do something or go somewhere I have to worry what problems I am going to have. If I ran my business like this I would be out of business. Needless to say I won't be going back to this mechanic ever again. As for the roof, these guys just started my roof so please pray for me.