It’s smarter to learn from the failure of others than from your own. German telecom giant Deutsche Telekom was kind enough to teach us a lesson this weekend how NOT to prepare for a crisis. Early Saturday morning, a “database error” caused a major blackout of their mobile voice and data services, leaving millions of customers in Germany and abroad with no signal for hours, some for the entire day. What appeared to be a worst case scenario already for the cell phone carrier, was topped by a gaping hole in its notification plan. According to media reports, that is.