Loss of soil support
Water moving beneath a slab can carry away soil and leave voids. Settlement can also occur when fill placed during construction compresses over time. Different causes can produce similar-looking low spots.
Look for drainage clues
Check downspouts, runoff paths, water collecting at the garage and erosion along slab edges. Take photos after rain if it is safe to do so. Water patterns can help a contractor understand why the problem matters.
Check the concrete itself
Note whether the panel is largely intact, whether cracks divide it into loose pieces and whether adjoining sections are moving too. Those details affect whether lifting can produce a useful result.
Do not ignore the garage transition
A low driveway approach may direct water toward the garage or leave a sharp lip. Ask how the proposed finished elevation will affect the threshold, door clearance and runoff.
Possible next steps
A contractor may assess slab lifting, replacement or related drainage work depending on the conditions. Explain the symptoms and request a project-specific recommendation rather than choosing a method solely from an online description.