A sump pump and a drain are not competing versions of the same thing. In many systems they serve complementary roles.
French drains collect or redirect
A drain captures water and channels it toward a suitable outlet or basin.
Sump pumps lift and discharge
Where gravity drainage is insufficient, the pump moves collected water to a discharge location.
Why design matters
Collection without safe discharge or pumping without collection can leave the original problem unresolved.
What to do before hiring
Photograph the affected area and record when moisture first appears. Ask the person assessing the basement to distinguish water entry from condensation or plumbing, explain what the recommended work will accomplish, and identify the discharge route for any collected water.
If you see significant wall movement, widespread damage, or suspect an electrical hazard, arrange an appropriately qualified assessment before proceeding with routine waterproofing.