The answer to 'when to replace leak repair' is that leak repairs should generally be replaced when the leak is recurring or the repair is no longer effectively stopping the leak. Recurring leaks often indicate a more serious underlying issue that requires a full replacement rather than just another repair. Additionally, if a repair is showing signs of wear and tear or is no longer providing a reliable seal, it's time to consider a replacement.
Factors to consider include the age and condition of the plumbing component, the frequency of leaks, and the effectiveness of past repairs. In general, it's best to replace a component if you've had to repair it more than once or twice, as repeated repairs are often a sign that the part is nearing the end of its lifespan.