I used Google Docs heavily for a few years. Then one day, about two years ago, they disabled offline mode. Guess what happened to me a few weeks later? Yup, I was in some situation with no internet access and needed a document and couldn't get it. I dropped Docs like a hot rock and switched to Dropbox the next day. (Granted, they now have offline access once again, through the very nice Google Drive. But, you know, "screw me twice," and all that.)
OTOH, I use Maps all the time, and Translate and YouTube. I arrived on this page via Google Reader and am entering this comment via my Nexus 7. So clearly they know how to make (or acquire) some good products.
Final note: Google relentlessly a/b tests everything. They know exactly how many people are rejecting the GMail redesign, or how many uses they stand to lose by killing iGoogle. Sometimes I think these cold, rational decisions backfire, as they annoy a vocal minority or misinterpret the reasons for the test results.