Most fences can be mended at a fraction of the cost of a new one. often if done properly, can be stronger than before. However if your fence is beyond repair. a new one may be the best option. Rest assured that when we build fences it will be done properly, because we are prepared to put in the hard work.
Often we see fences that have failed prematurely, the reason is the predecessor did not have the knowledge, or the contractor wanted a quick buck without to much effort
Another reason for premature failure is DIY people looking on line, often taking the advice from articles written by people with very little knowledge.
For a proper job use DM & PA COOK