Out of time ordered correlators(OTOC) in certain large N systems can be described by scramblon modes. In large N limit, scramblon exchange dominates, while scramblon interactions are suppressed by 1/N. However, we are going to discuss certain types of scramblon loop corrections, which cause a dramatic breakdown of scramblon exchange approximation, much earlier than naive expectation. These effects are related to the distinctive exponential growth behavior of scramblon propagator. Interestingly, while these effects are significant in high temperature/weakly coupled systems, they get cut off in finite temperature systems by ballistic growth. In language of holography, these effects will get suppressed in graviton-exchange dominant region. We will also comment on other types of quantum fluctuations and their relation to wavefront broadening phenomena.