Multisite and plugins options

Back when Multisite first appeared, there were multiple blogs in a single site. The *_site_option functions are from that older Multisite era.

Now in current Multisite you have multiple sites in a network, so the meaning of “site” has made a confusing change.

In the context of these functions, think of them as network functions and it may make more sense. They create and update options which are not associated to a particular site in your network, but are global to the whole network.

If you want unique, per-site options, use the regular add_option, update_option, and get_option.