keep emotions out of business at pinnacle of success of one of my education portal , i had about 2385 registered users ( university students focussed portal ) . I was feeling bit low perhaps because of some personal issues . I had some strong urge and I ran query which deleted every tables in the database, immediately causing havoc. I was out of my senses ( not drunk as I don't drink ) and I realised bit late that it was all gone . Last backup I had was of about 3 months older with 1700 users and lost incredible amount of valuable data. lessons learnt - 1. emotions are good but business decisions should be well planned and should never be taken when you are emotionally unstable. 2. take backup of your digital data frequently or else you will suffer sooner or later . 

business learnings decide and do things after giving proper thoughts to it. else you will waste time and regret ( sometimes at least ).