Trust, but do check

In most dangerous jobs and situations people are trained to work in pairs and check each other; the buddy check. This check is to make sure you did not do something stupid or forgot something. Humans are just humans and humans make mistakes.

Always take your buddy check seriously. I have had seen people failing in doing there buddy check, resulting in climbing harness buckles not being doubled backed, screw carabiners left open, incorrect attaching them self to ropes and having twisted harness causing side ways loads on there equipment. 

During work or hobbies this might be due to work stress, haste, distractions, excitement or carelessness. I have had people saying 'I trust you' and skip the buddy check. Don't skip it! Humans makes mistakes. regardless of you experience. Most mistakes are made by beginners or by highly experience people. Highly experience people loose there attention on safety, because of there experience and the countless time it went well. Two people seriously checking each other should reduce the chance of making human mistakes, so do your buddy check properly and stay safe!