Could be genetics, could be balance of nutes... thin fingers and not developing successively more fingers each growth node is a sign of less than idea fertilization, too.
3-5-7-9-11-13 etc... whether it is missing 1 of those tiny fingers etc is less of a concern, but if you don't have a normal progression up to at least 9 fingers most of the time, there's a higher chance it is self inflicted.
if this plant looks healthy and happy till the end, less likely it is fertilizer balance. At that point you lean toward blaming genetics, lol. If it ends up with toxicities and leaf symptoms, might be wise to re-assess fertilization choices, which you would do anyway.
on its own, it's not enough to react to, imo. I can't recall any of my plants not progressing to at least 9 fingers, though... 200+ plants at this point and the only time i see that shit is on a revege or an extremely stressed plant. Training/pruning can reset that 'finger' progression too. It may have 13-finger leaves, then you top it or train it and new growth shows 5 and 7 finger leaves, initially, then should progress back up to what you saw before that training/pruning. That's perfectly normal. Stress definitely impacts what results in this regard.