[belorn]

The question is what customers of monitoring systems expect from the monitoring. Do pingdoms explain what a failure means, or are they only providing data and then its up to the customer to interpret that data.

Multiple ping locations is helpful in bringing more data points, but it doesn't address the problem of explaining what the data means. For example, pingdom could provide triangulation of the failure if fault identification was part of the businesses model of monitoring.

I would describe the criticism of pingdom as a failure of expectations. Pingdom is not a security service, a monitoring service, or fault identification service. They are a single test, and the data you get back is useless unless interpreted and verified.