Not quite correct.
Sodium hypochlorite, the active ingredient in bleach, only kills mould it comes in contact with. If the bleach doesn't come in contact with all the mould, then it won't be fully killed. It isn't a systemic fungicide, which means it will travel through the whole of the living parts killing it all.
It readily kills mould on the surface of things, but won't kill the mould which has penetrated materials...such as mould hyphae which has grown into grout or wood.
Hyphae is the filament or growing material (think of it like a root or stem in flowering plants) which makes up the mould/fungi and when one section of hyphae is killed, such as being in direct contact with bleach, any hyphae which is still living will continue to grow.
Google scholar has many papers which assess the efficacy of bleach/sodium hypochlorite on moulds/fungi.
It is also worth noting that weak/diluted sodium hypochlorite solutions is used within the food industry to sterlise food products which may have fungal and bacterial pathogens (including moulds).