There's nothing wrong with a plan, but remember Von Moltke's famous dictum that no plan survives first contact with the enemy. The danger is a plan that seduces us into thinking failure is impossible and adaptation is unnecessary - a kind of โTitanic' plan, unsinkable (until it hits the iceberg).
Tim HarfordSuccess Comes Through Rapidly Fixing our Mistakes Rather than Getting Things Right the First Time.
Tim HarfordIf the whole process of learning from failure means discarding stuff that's not working, but in fact, our natural reaction is to keep going, to throw more money behind it, to throw more emotional energy behind it... that's a real problem.
Tim HarfordLoss aversion is a really disproportionate anxiety about stuff that doesn't matter very much. So for instance, if you lose $5, you feel really bad about the $5 you've lost. You're cursing yourself. You're going through it again and again. If, on the other hand, you find $5, you go - hey, great, five bucks. And you've forgotten about it really quickly.
Tim Harford