Reliability is one reason, residential internet and power is less reliable than commercial. You will have to provide UPS to everybody. Plus, if employees are lo

Reliability is one reason, residential internet and power is less reliable than commercial. You will have to provide UPS to everybody. Plus, if employees are located together then there is risk that regional power outage could take the system. Then there is latency. Most apps talk to a data store, which is now separated from clients. The load balancers are going to be separated from the backend. Also, database servers tend to be beefy servers so either need to shared it or someone hosts a rack. Another is that need write software to really be distributed. There is difference between distributed when things break and distributed all the time over the internet.