And yet there are a lot of active exploits targetting Windows. If your logic was sound, given that Windows is by far the most used system it should also be the most secure: then again I invite you to research the subject, security reports often show that it is more vulnerable than most linux/unixes. I find 7 to be an acceptable OS (and I still use it everyday) but blindly beliving that Microsoft ecosystem is secure because it is Microsoft's is a mistake.