The answer to 'how long does leak repair last' is that a professional plumbing leak repair can typically last 5-10 years or more, depending on the type of repair and the underlying cause of the leak. A properly done leak repair that addresses the root issue, rather than just patching the symptom, will generally have a longer lifespan.
Factors that can affect the longevity of a leak repair include the material and method used, the age and condition of the plumbing system, and whether the root cause of the leak was fully addressed. Repairs to older pipes or those with underlying corrosion may not last as long as repairs to newer, healthier plumbing. Regular maintenance and inspections can also help extend the life of a leak repair.