Bugs. Grotty little cretins that lodge in your windpipe, frighten girls and ruin family picnics. Eat your greens like your mother told you to and bugs are kept at bay - the medically related ones, at least - but even a prize cauliflower would wither in the face of a digital creepy-crawly, which can cause games to crash and characters to morph into lamp posts.
It's not only end users who gnash their teeth in frustration; developers also scream "D'oh!" when quality assurance (QA) goes pear-shaped.
"The one that really nailed us was when we shipped Matrix: Path Of Neo and the McAfee virus killer incorrectly identified the game as a virus," says developer Dave Perry. "Needless to say, people were freaking out, thinking the game contained some old virus from the '90s, when it was McAfee simply getting it wrong. That was painful and too late when discovered."
Bugs have been around since the dawn of computer technology. In 1947, a Harvard University boffin was trying to fix a primitive machine that was acting up. As it turned out, a moth had become lodged inside the device, leading him to make an entry in his log - "First actual case of bug being found" - and enabling games journalists to make pun-riffic jibes about insects for decades to come.
In this day and age, bugs and boo-boos are depressingly commonplace in PC games - from Vampire: The Masquerade's stuttering cadaver of an engine to Oblivion expansion Shivering Isles and its vanishing objects. Both games were treated with patches, but - let's face it - a bandage is meagre compensation after getting stabbed in the ribs. Even the finest games have their share of hiccups - randomly floating characters, wonky physics, motionless guards. But why so?
"All software releases have bugs, and no program is ever bug-free," explains Californian games tester Zachary J Slater, who has tinkered with such titles as Halo 2, Doom 3, Quake 4, Wolfenstein: Enemy Territory and Soldier Of Fortune.
"The more variables there are in a piece of software, the more bugs will pop up. For example, a cellphone game could conceivably have far fewer possible bugs than a larger, more complex game like Unreal Tournament. Think of how many weapons are in a first-person shooter, and how many different situations you could get into with those weapons. You can't possibly think of every situation, especially in multiplayer games. All you can do is mitigate the bugs, taking care of as many serious issues as possible. It's all about the math of money, testers and time to create a game with as few bugs as possible."
Some developers reckon it's partly the fault of gamers. Perry explains: "Complete testing is almost impossible, as there are so many people out there, in so many countries, with so many configurations. They'll say, 'Your damn game won't install properly!' You then find out that the dude has 16 CD-ROM drives installed. Yep, we never tested that."
Nevertheless, buggy games seem more prevalent today than ever before, and certain publishers are in the firing line. Three recent Ubisoft titles are especially flaky on PC: Silent Hunter 4: Wolves Of The Pacific, Splinter Cell: Double Agent and Resident Evil 4. Bombarded by customer complaints, Ubisoft issued patches for all three, but it didn't do much to calm tempers. Buy a new car and you expect it to work 100 per cent - why not the same with games?
"Big publishers spend as little time as possible on QA - enough to meet console compliance and their internal processes for PC games, while still retaining the day-one buyers in general," says Slater the tester. "Strangely, the people who buy the game months down the road will have a better experience, due to patches and additional (often free) content. You'll notice the complete opposite from smaller companies like id, Epic and Valve. They have to go the extra mile because their reputations are at stake, but something like EA's Madden franchise is large enough that it can get by on name alone."