Probably the scariest thing about making a soufflé is folding in the egg whites.  You just finish beating the egg whites to get all this air into them, and then you have to take this fragile fluffy cloud and fold it into some really dense heavy stuff (your soufflé base), and you're cautioned that if you do it wrong, your soufflé won't rise and you'll have an ugly mess on you hands (or, more importantly, in your dish!)