ChrisC;4283413 said:
Plenty of artists delay their tours or cancel them when their voices aren't up to it. They do this out of respect for the audience. They don't just go out and fraudulently perform. It is categorically not the "only way to do it".
They do this not only out of respect for the audience, but mainly they do this for monetary reasons.
They want to avoid giving ticket refunds to the audience if they, for one or another reason, lip-synced during their shows.
Especially, when their on-stage performance is not really physically demanding, and the audience expect from them fully, live vocals.
Look, for example, at the audience’s outrage which was caused when the Italian operatic tenor Luciano Pavarotti lip-synced during one of his concerts in Modena (1992).
Ticket refunds were the immediate result of Luciano Pavarotti’s lip-sync at that concert (aside from the bad publicity that he suffered at the time because of his exposed lip-sync).
Or, look at the very recent case (in 2019) of the American rock band KISS when ticket refunds were given to certain people who went to see them live.
These people demanded and eventually got their ticket money back because they felt cheated by the lip-sync of KISS in one of the band’s concerts.
But people appear to be more forgiving and lenient towards lip-sync if the artist also dances a lot while performing (and that is the case when it comes to Michael Jackson’s lip-sync during the HIStory Tour).