To borrow an example from native desktop applications, it is quite common to have poorly performing Line of Business (LoB) applications on corporate desktops. The desktop will probably be old and underpowered. The networking back to the central database may be slow because the connection might be over a remote link to a regional office.
With a badly written application that is too chatty with the DB, it can be better, performance-wise, to run the application on a server close to (or on the same server as) the DB. Perhaps, the application workspace and DB servers can be in the same server rack at the data center and connected by a Gigabit (or 10 Gigabit) Ethernet.
The user can then use a remote desktop connection or Citrix ...
