Thanks. I am all for automated alerts, but not everything can be automated easily. And false or too many alerts are a big problem, so training yourself to look at a couple more comprehensive dashboards every day (ideally with red markers for stuff that is unusually bad) instead of every freaking alert can be a less time-consuming approach (or at least complementary.

And Alerts are often just a "first hint" that sth's wrong ("Cart Addition Rate down excessively on Product Detail Pages in Category X") - they are rarely conclusive, so the next step can then be to look at such a monitoring dashboard to get a more complete picture.

As for the "give a general sense of what 'normal' is" - I have to say that this was the case for me for several clients in the past.