I recently moved in to my new place, transferring home to Ottawa after 7 years in the middle of nowhere. I had Evu out west, but no other Bell services. They screwed up my initial phone install 9 hour "window", and did not actually schedule a tech to come, and did not call me to cancel. I finally got my phone after another week, then my modem another week later. The phone tech appointment was narrowed down to a one hour window, the most I would agree to given one wasted day. Evu, surprisingly, was most on the ball installing the day after I called, doing everything as asked and very well, and within the four hour window.
When I complained to Bell about the phone FUBAR (it was far more involved than the brief play by play above), they offered me a $50 credit and a month free internet. I turned them down. Then $100 and three months free inet. Still not enough for the 9 hours of my time waiting for an appointment they never intended to keep. Then EVU, the only division that got it right, threw in two months free, another $150 roughly. So, to keep me as a customer for the three services, they gave me about $330 worth of credits, or about 3 months free for all.
The screwup was a bit more than many have to deal with, trust me, but they are willing to go pretty far to retain their customers in terms of credits.