Spaghetti Code is the term programmers use for source code that is too convoluted and big to understand.
Now we live in a world of consumer electronics, with gadgets, appliances, cars, and homes, all enhanced with some form of silicon logic. The change was fast and we're still trying to catch up with all these technological marvels. Programmers are having the same problem. They can't spend any time fixing old mistakes when there's new code to write.
Over the decades, millions of programmers have written billions of lines of code around the world. A majority of these programmers have some training, but many are trained on the job and learn as they write code. Mistakes are made, but they are shrugged off as a slide down the learning curve. It can always be fixed later.
But a lot of it never gets fixed. Over the years, new programmers add their own fixes and features, and soon the source code is too big for anyone to understand. If there's any fundamental problem in the code, it's hard to fix, and it's getting harder all the time.
When an engineer builds something, like a train, they have to obey the laws of physics and make sure the train works reliably and safely. If they make a mistake, it could be disastrous. Computer programmers usually don't have the same pressures. If they make a mistake, their technical support department will get a lot of calls, but buildings won't collapse.
Computers fail all the time, and every system crashes periodically. You are inconvenienced everyday by these system crashes, at least indirectly. I'm sure you've had to wait on the phone because "the system is down" or "acting funny." We already accept computer problems, but few people want to get rid of computers.
Y2K just adds more problems to an already complicated world of computers and microchips. The year 2000 will create a few additional problems, but they will just be more of a nuisance than a disaster.