when to think about using a cdn for your app? maybe when youre worried about speed or reliability, that sort of thing.

ive been working on optimizing a few web apps lately and the topic of Content Delivery Networks (CDNs) keeps popping up. we're not talking about huge, global traffic yet, but for specific assets like images and static files, it seems like a good idea. what are the key indicators or thresholds you look for that signal its time to seriously evaluate integrating a CDN? are there specific performance metrics or traffic patterns that make it a no-brainer?