r/logisim

I'm trying to map out a circuit diagram for a railway crossing, and I noticed that "improvised" SR flip-flops (made of two cross-connected NOR gates) behave weirdly compared to "proper" ones. At the start of a simulation, they're both giving an error output, which the diagram treats as a high until I've clicked all four ON and OFF buttons, after which everything starts functioning properly. Is it just a Logisim quirk or am I actually doing something wrong here?