There are lots of lessons in the internet's limited history that show poorly conceived defaults are the most common and dangerous mistake. Microsoft let Frontpa

There are lots of lessons in the internet's limited history that show poorly conceived defaults are the most common and dangerous mistake. Microsoft let Frontpage Extension credentials default to the domain name and a blank password through multiple major versions, without any prompt to change anything (you had to seek out the settings, and it wasn't even obvious where they were). Throughout the late 90s and early 00s, entire hosting companies were continuously compromised because of this, along with nearly every school district in the US and tons of major universities. Schools typically had the worst security and most available processing power and bandwidth, already making them the preferred targets of script kiddies everywhere. That exploit was single-handedly responsible for hundreds of thousands of bots (and more likely millions in later years) which wreaked havoc on the internet as a whole -- these were the days when a handful of bots on good connections could take down the Amazons of the world for lengthy periods (days, not hours). That they let it go on for so long was comical at the time, but in hindsight seems criminally negligent.