Meaning, the disease killed DYING people a few months earlier than expected.   Ex-cases that died don't help reaching the herd immunity.  Whether the IFR is 0.1% or 1% or 5% it doesn't matter. Herd immunity is the only way forward.  Herd immunity is the only way forward and that's why only the IFR matters. If we would know the IFR and the number of ex-cases needed to reach herd immunity, we would know how many people will die until it's over.