What makes Flash crash?

Adobe's Flash has had a lot of bad publicity lately, mainly from Apple, but also from Microsoft too. Both companies report that it is the cause of many of the crashes that users experience on both Windows and Mac OS X. Ed Bott has written a couple of interesting articles too and How secure is Flash? Here's what Adobe won't tell you, and Sorry, Adobe: Flash is the new Vista are well worth reading. In one of those articles he says that Flash crashes once or twice a day on his wife's computer. He didn't say whether his computer was OK, but presumably it was or he would have said. I don't have any problems on my computer and Flash doesn't crash. The question is, what makes Flash so unstable on some computers, but not others?

I don't know what the answer to this is, but surely it must have something to do with other software destabilising it. It is unlikely to be the hardware because Steve Jobs has said that Flash crashes a lot on the Mac and nowhere is the hardware more tightly controlled. It's not like the Windows world where anyone can put Windows on any combination of hardware components cobbled together in someone's back bedroom by someone that barely knows how to assemble a computer. It's got to be software.

Perhaps it is some other web browser plug-ins and Flash clashes with something else that is installed. I'm not a fan of browser plug-ins, add-ons and toolbars and have hardly anything installed. Maybe that's why I don't get any Flash crashes. (The one plug-in on my Mac is ClickToFlash, which lets me run Flash only when I need it.)

As a general rule of thumb, it's always a good idea to install the minimum of software and the more you have, the worse the computer sometimes becomes. These days I often install software into a virtual machine. The virtual machines run either Windows or Linux and they run on Windows and Linux PCs, so I can run Windows on a Linux PC, Linux on a Windows PC, Windows on Windows (here) and Linux on Linux, and both Windows and Linux on a Mac (see here). (It would be great if OS X ran in a virtual machine too.) I only install software on the computer if I've tested it first and it is indispensable.