In The Long Run Meaning

(idiomatic) After a very long time; eventually; over a long period of time; more generally.

Example: 1923, John Maynard Keynes, A Tract on Monetary Reform, ch. 3:
  In the long run we are all dead.
1951, Arthur C. Clarke, The Exploration of Space, p. 111:
  If we have learned one thing from the history of invention and discovery, it is that, in the long run — and often in the short one — the most daring prophecies seem laughably conservative.