Basement crack repair seals the exact spot water uses to get in. A poured wall does not leak everywhere at once. It leaks at 1 or 2 cracks, and closing those stops the water. If water arrives along the whole floor line instead, that is hydrostatic pressure (opens in a new tab) and a different job. Telling the two apart takes about forty minutes.
Akron cracks walls every winter. Wet soil freezes against the foundation, swells and pushes in. Water inside the crack turns to ice and grows 9% bigger. Frost heaving (opens in a new tab) does that dozens of times a season, so a hairline becomes a leak.
We inject at low pressure so the resin travels right through the wall. When it shows on the outside face, the gap is gone. If the crack runs sideways and the wall bows in, that is foundation repair first. If the crawl space under the same house is damp, that is crawl space encapsulation.