The Prophet of Allah ﷺ said:

سيأتي زمان على أمتي يحبون خمسا وينسون خمسا، و يحبون الدنيا و ينسون الآخرة، ويحبون المال وينسون الحساب، ويحبون الخلق وينسون الخالق، ويحبون الذنوب وينسون التوبة، ويحبون القصور وينسون المقبرة
“A time will come when my Ummah will love five (things) and forget five others: they will love this world and forget the Hereafter; they will love money and forget the Reckoning; they will love creation and forget the Creator; they will love sins and forget repentance; they will love palaces and forget the grave.”

We should realize that bid’ah is different from other types of sin because the person committing it has good intentions – they believe/feel/have drawn the conclusion that they are doing something which will bring them closer to Allah and that Allah loves. From that perspective, I don’t see how a layperson, who has heard of a practice or sees a practice being performed by his teacher, etc and follows that – would be guilty of committing shirk. Also we have to realize that there has historically been a difference of opinion on ‘bid’ah hassanah’ and la inkaara fi masa’il ikhtilaafiya – as laypeople (and not scholars) if we find someone acting on an issue on which there is legitimate ikhtilaaf it is not our place to condemn or reject that. An example would be saying dhikr in unison which even Imam an-Nawawi has permitted. (Note: I’m talking here simply about people saying dhikr in one voice, not about hadras etc).

As for the one who originated an act of bid’ah- again, it depends on their intentions. I really doubt that such a person thought to themself ‘I know better than Rasulullah (salAllahu alayhi wa salam) about how to get closer to Allah.’ It is more likely that they interpreted some texts in such a way that they feel the act they are performing is legitimate. Or, it is possible that they performed an act and later on it became ritualized into a practice by their students/followers. If however, the person does have the belief of ‘I can improve on the Shari’ah’ then I can concede to the pt. being made above.

A really beautiful pt. that I have heard Sh. Mokhtar mention on the issue of bid’ah is that you have to really look at the person engaging in it, what their intentions are and their understanding and level of knowledge. Also, bid’ahs are at different levels and we have to think about the probable consequences of our actions and the best way of dealing with them. A layperson who for example does some type of dhikr that is not masnun regularly, because they had learned about it from some shaykh – such a person is different from someone who, for example rejects Hadith in its entirety or comes up with their own crazy ideas. Each should be treated differently depending on the particular circumstances, Allahu a’lam.

salaam