https://marco.org/2008/01/21/most-new-windows-machines-come-loaded-from-the
Most new Windows machines come loaded from the factory with promotional software that most Mac users would consider adware. It’s a slippery slope to malware adware (as opposed to the non-malware adware that ships with these machines) from there. The simple truth is that Windows users are more accustomed to being annoyed by their machines.
— Daring Fireball: Why the Mac Doesn’t Seem Viable for For-Profit Malware