What happens if you beat egg whites with a wooden spoon instead of a whisk?

In our cookery, we were making souffles and one boy beat up his egg whites without a whisk like everyone else but with a wooden spoon and he had less mixture and I don't think his souffle rose. Why is this? Is it because the air bubbles in the egg whites collapse with the spoon? I was just wondering, he's not really much of a cook.