You must construct additional pylons

[Justin Bieber]

This is possibly the most annoying phrase in the real-time-strategy game Starcraft.
The basic objective of Starcraft is to make a big army to destroy your opponent, however you have this army-size limit known as supply that can only be increased by building a specific building, and for the alien faction protoss, that building is the pylon. So every 2-4 soldiers you build, you most build another pylon to sustain them. If you forget, a voice says YOU MUST CONSTRUCT ADDITIONAL PYLONS, and at that point, you realise that you cant build any more guys until you send a worker to build the pylon, and then wait for the pylon to finish. Then, 4 soldiers later, you will have to build ANOTHER one.
What makes this phrase especially annoying is how often the guy says it if you forget to build them, because soldiers of the protoss race take up so much supply, and their pylons provide such little supply.