Remark 9.2.1.11. Let $\operatorname{\mathcal{C}}$ be an $\infty $-category, let $C \in \operatorname{\mathcal{C}}$ be an object, and let $W$ be the collection of all morphisms $w$ in $\operatorname{\mathcal{C}}$ such that $C$ is $w$-local. Then $W$ contains all isomorphisms and has the two-out-of-three property. Moreover, it is also closed under retracts (in the $\infty $-category $\operatorname{Fun}(\Delta ^1, \operatorname{\mathcal{C}})$).
$\Newextarrow{\xhookrightarrow}{10,10}{0x21AA}$