The most valuable piece of advice I've ever gotten about investment and management is that there is no such thing as a perfect plan. It's easy to get caught up in the idea that if you can just come up with the perfect solution, then everything will be fine. But I've found that life doesn't work like that! Instead, being flexible and adaptable is what's going to keep you afloat when things go wrong. I always try to keep in mind: "No plan survives first contact with reality."