Whatever is in short supply will be in great demand. There is no demand once the new supply arrives. After selling the new supply at a loss, demand resumes. Only someone who understands something completely can explain it so that no one else can understand it. Good judgment comes from experience.
Experience comes from bad judgment.
The most heavily traveled streets spend the most time under construction. Every solution breeds new and bigger problems. Nature always sides with the hidden flaw. Nothing looks as good close-up as it does from far away. In any given set of circumstances, the correct course of action is dictated by subsequent events.