Why do Facebook and Instagram always crash together?

Facebook and Instagram crash together because they are both owned by Meta and share the same backend infrastructure. When Meta's core systems go down, such as their servers, data centers, or internal networking (like the major BGP routing outage in 2021), it affects all of their platforms simultaneously, including WhatsApp as well. The apps rely on shared services for authentication, data storage, content delivery, and other functions. So even though Facebook and Instagram appear as separate apps, they are deeply connected on the backend. A failure in a shared component like a database cluster, load balancer, or configuration system will bring down multiple platforms at once rather than just one.