If your trip is 14 days long but you only move between cities twice, buying individual "point-to-point" tickets is significantly cheaper.
If you are mostly staying in Tokyo or Osaka and doing local day trips, the pass is a waste of money. when to buy jr pass
If you are only exploring one area (like just Kyushu or just Hokkaido), a Regional JR Pass is much cheaper and more effective. If your trip is 14 days long but