Planning is absolutely essential. However, "no plan survives contact with [the enemy]/[reality]/[stakeholders]/[users]/[etc.]" You have to start doing things

Planning is absolutely essential. However, "no plan survives contact with [the enemy]/[reality]/[stakeholders]/[users]/[etc.]" You have to start doing things at some point, and revise your plans continuously. It's a delicate, interdependent dance. The worst working situations I've been in almost all had to do with either lack of planning or refusal to abandon a clearly flawed plan. It's exhausting how many people fail to recognize when they need to change their behavior in one area or the other. It's not one or the other, it's both.