It instantaneous temperature is going to be a function of many uncontrollable variables: weight, shape, air speed, the list is long.

Unfortunately, rates of evaporation, freezing, or melting are difficult to make in any meaningful way - too many uncontrollable variables come into play.

It is easier for analysts to forecast earnings if they know that uncontrollable variables won't affect the numbers.

But measuring rates of solids has so many uncontrollable variables that the results are essentially useless.

Your system has any number of uncontrollable variables.

One had to monitor all the uncontrollable variables that affected the situation.

To them, the human factor was an unquantifiable and therefore uncontrollable variable and, in time, technology seemed bound to eliminate such performance problems.

On the other hand, it was a business subject to other uncontrollable variables that the rest of the retail sector did not have to worry about.

There are 'uncontrollable' variables that could result in many different scenarios.

The customers are any restaurant's last, uncontrollable variable.