It does but the problem is they gave different heroes and extra turn in their kit for free and it can proc twice because of this 

It can fire indefinitely and it's not normal

It really doesn't need to be nerfed. It 20% for an extra turn, which logically means 80% of the time it doesn't work. Characters like Peira and Ran are more likely to proc it since they already take an extra turn -- so the artifact outside of that proc chance is entirely useless and you for the misfortune of having it proc often want it to be nerfed over some bad matches is childish.

Skill Issue

The artifact is fine as it is, and does not need a nerf.

The artifact is good but the mechanic bad implemented IMO.

If ran gets a r&l proc while S2->S3 he should have just one extra turn, not two. He already got his extra turn anyways.

Yes, it need nerf. It's should proc only in normal turn, not double extra turn.