I think what she/he is saying about the progressing too fast would lead to no correction error means that when you level up a card just for 1 day ex.(level 1 to 11-12) would lead to a system getting suspicious on you and you probably will get a problem like *no internet connection* this will lead you too more likely a ban but you can still play but offline (you cant access clan/guild cannot buy anything *real money* and cant participate events)
It happend to me last year and last 3 months
If this isn't the answer well i dont know lol atleast i explained a little consequences upgrading too fast