Not necessarily. One of the most common defenses stores raise is that a hazard was 'open and obvious' — that you should have seen and avoided it. But this argument is frequently disputed, and it does not automatically defeat a claim.
Even where a hazard was arguably visible, a store can still be responsible if it should have expected that customers would encounter it anyway — for example, a spill in a busy aisle where shoppers are looking at products, not the floor. And in California's pure comparative fault system, even if you were found partly at fault for not noticing, that only reduces a recovery by your share; it does not bar the claim.
So being told a hazard was 'obvious' is not the end of the road. The store's own failure to keep the area safe still matters, and the footage and sweep logs can establish its negligence. It is worth having the situation reviewed rather than accepting the store's position.