I won't pretend to be an impartial observer tonight.
My Roosters are playing the Dolphins in the NRL preliminary final, with a place in next weekend's Grand Final on the line.
Preferably by enough that I can enjoy the last ten minutes.
I'm not about to change teams because somebody else had a better night.
With the AFL Grand Final tomorrow, I'm alone in getting a little bit carried away this weekend.
But it can be an ordinary way to be an investor.
Imagine two football clubs having disappointing seasons.
One has a young squad, a sensible development plan and players who are getting better. The results aren't there yet, but you can see what the club is building.
The other keeps promising that next year will be different, while making the same mistakes.
Only one has given you a reason to believe it.
A falling price doesn't, by itself, tell you that the business is broken.
Nor does a rising price prove that everything is going.
The price is what other investors are prepared to pay, right now.
You need to look at the business.
Consider a hypothetical retailer spending money on a new distribution centre. Profits might suffer while it gets the facility running. If customers remain loyal and the investment does what management said, patience might be sensible.
Now imagine another retailer losing customers because a competitor offers something better.
We liked the company enough to buy it.
Leave one eye closed, at least until the final hooter/whistle/siren.