I disagree. Communication is the most important. It's the number one cause of failed software project. Miscommunicated features, capabilities, scope, failure

I disagree. Communication is the most important. It's the number one cause of failed software project. Miscommunicated features, capabilities, scope, failure to name a few. My favourite is the last one. Not standing up and recognizing that an approach is not working due to fear has to stand out as a big one.