It's Friday and you are looking forward to the weekend, but an evil genius has locked you in a room. The door to the room is protected by a special electronic lock with four identical buttons equally spaced along the rim of a circular dial.
Each button toggles an internal switch within the mechanism. You can attempt to open the lock by simultaneously pressing any set of the 4 buttons which will toggle the corresponding switches. If you are lucky enough to thereby align the switches so they are all on or all off, the lock will open. Otherwise the dial begins a spinning cycle that lasts for 1 full minute. When it comes to rest you have no way of knowing which button(s) you pressed previously.
Your captor is returning in 15 minutes. Is there any possible method you can think of that will GUARANTEE that you can open the lock in less than 15 tries? If it is not possible, then let me know why that is the case... so I don't waste my time.