All LLMs have some random aspects. Training alone relies hugely on many factors (e.g. initialization of paramters, order of training data, hyper paramters, etc

All LLMs have some random aspects. Training alone relies hugely on many factors (e.g. initialization of paramters, order of training data, hyper paramters, etc.). In evaluation (afaik this applies to recent models as well) you pick the continuation based on chance and not always the "best". But evaluation is the result of the training process, so all the randomness from that factors in as well.