u/Enfiznar

I preventively sprayed with peroxide, but I'd like a confirmation

Both jars have the same substrate, prepared together, sterilized together, in the same kind of jar. Both were inoculated through G2G, at the same time, from the same grain, everything I can think of was the same. Yet one is about to finish colonizing, while the other isn't even fluffy. What may be the reason?