What is the butterfly effect in travel novels?

For example, when you returned to the Three Kingdoms, you became "Lu Bu", because you would know what happened to Lu Bu, and you would certainly try to avoid this situation-for example, the Fengyiting incident.

If Lyu3 bu4 doesn't appear in Fengyi Pavilion, the relationship between Dong Zhuo and Diao Chan will change again. If Lyu3 bu4 doesn't kill Dong Zhuo, it will be even more difficult for Cao Cao and his large number of heroes to get ahead. If Cao Cao and his team ... the whole world ...

During the Napoleonic Wars in France, they lost a horseshoe because of the loss of an iron nail, and when they lost a horseshoe, they broke a war horse and died. The demise of a country turned out to be due to the loss of an iron nail.

this is the so-called butterfly effect.