Leaders own the outcome, not just their part. “I did my slides” doesn’t help if the project failed.

Doing your piece and then standing clear is how a group fails with everybody technically blameless. Owning the outcome means your job is not finished when your part is finished, it is finished when the thing works, which sometimes means helping with somebody else’s section. That is the real difference between a member and a leader, and it has nothing to do with a title.

Before the next deadline, check the piece nobody has mentioned in a while instead of polishing yours. Offer to take some of whatever is behind. Judge yourself on the result rather than on your share of it.