We live in a chaotic world.

How long does it take to go from your home to the shops? Does it take the same time every time?

It is hard to take exactly the same trip every time, something usually happens to change things. You take different steps, people get in your way, etc.

In fact it is nearly impossible to do something the same every time.

So just one measurement may not give you an accurate picture.

Example: Sam is good at shooting baskets, Hunter is not so good.

The coach tests them out:

So far Hunter looks better than Sam.

But the Coach knows statistics, so gets them to try some more. Here are the results:

Sam 0 1 1 0 1 1 1 1 0 1 7/10
Hunter 1 0 1 0 0 0 1 1 0 0 4/10

Even after 4 shots they seem equal, but after 10 shots Sam is in the lead.

The moral of that example: the more "tests" you take, the more accurate will be your results.

Statistics is