Here's why:

* Nonmetals: While many nonmetals are indeed highly reactive (think oxygen, chlorine, fluorine), there are also some that are relatively unreactive, like the noble gases (helium, neon, argon, etc.).

* Metals: Metals are not completely nonreactive. Many metals are quite reactive. Think of how readily sodium reacts with water, or how iron rusts (reacts with oxygen). There are less reactive metals, like gold and platinum, but even these can react under certain conditions.

Key Differences in Reactivity:

* Nonmetals: Nonmetals tend to gain electrons to achieve a stable electron configuration. They are often electronegative and readily form anions.

* Metals: Metals tend to lose electrons to achieve a stable electron configuration. They are often electropositive and readily form cations.

Summary: Both nonmetals and metals exhibit a range of reactivity, with some being highly reactive and others less so. Generalizations about their reactivity based on whether they are a metal or nonmetal can be misleading.