Why no reversing ticket?

It never ceases to amaze me that a rise in price can often result in a "speeding ticket" or "please explain" and yet a reversal of price creates no interest or official intervention.

I as an investor am equally affected by either a price rise or a price fall with the latter causing a great deal more angst than the former!  A price rise is a thing of joy and long may it continue to, but I would love to know what sometimes possesses otherwise intelligent people to sell a share at a lower price than may appear necessary.

So why a "please explain" when things are looking rosy and broadcast silence for a dark day?

I am sure that is easily explained by a quote from Donald Rumsfeld as follows:

There are known knowns.
These are things we know that we know.
There are known unknowns.
That is to say, there are things that we know we don't know.
But there are also unknown unknowns.
There are things we don't know we don't know.

My head now hurts, but if anyone can help me I welcome the enlightenment.

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