Like most trends, at the beginning it’s driven by fundamentals, at some point speculation takes over. What the wise man does in the beginning, the fool does in the end.
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It takes 20 years to build a reputation and 5 minutes to ruin it. If you think about that you will do things differently.
Why not invest your assets in the companies you really like? as mae west said, “too much of a good thing can be wonderful”.