There is an important thing in musicals that do not get the respect and appreciation. These belong to understudies, and if they did not exist, so many musicals would be cancelled. When the main actor is out for the day, the understudies cover for them, and a swing comes in to play the part that the understudies usually play.
Grace Morgan (Christine), Mary Kate Morrissey (Elphaba), Lisa Karlin (Leading Player), Sam Lips (Pippin), Adam Bayjou (Valjean), Talia Simone Robinson (Eponine), Eymard Cabling (The Engineer), and Andrew Maughan (Valjean) were all understudies. However, only of them was a standby, which was Mary Kate Morrissey- when you have a standby, a swing is not involved since the standby is not part of the ensemble. One of my actresses I saw had an incredible journey to eventually landing the main part.
It belonged to one of my Fantine actresses. I actually saw her in Les Mis twice- 2017 and 2019. Back in 2017, I only saw her in the ensemble, but for the tour she was also cast as 1st cover Fantine. In 2017, Melissa Mitchell, who I saw as Fantine, was the main actress. After she left, Mary Kate Moore ended up becoming the main Fantine. So when 2019 happened, Mary Kate Moore was still Fantine, and still was the main one when I actually saw the show that year. I was hoping I would get her, and I did.
So you see, in the same show, an understudy has the talent to eventually move up to to a lead role. Mary Kate Moore is one of the important ones to bring up. I saw her start as an ensemble member and later the main role. Whenever I think of that character, she is the one I talk about. After all, actors/actresses like her don’t get the respect and appreciation that they deserve.
Even Nick Cartell and Anthony Festa moved up- the difference was not in the same musical. Nick was in the ensemble of Phantom of the Opera, and was also an understudy as Raoul. He was my Valjean in 2017, and he actually ended up being one of top three Valjean actors. With Anthony, I first saw him in Wicked in the ensemble, and was an understudy for Fiyero as well. In 2019, he was my Chris. Both Nick and Anthony moved up from understudy to securing a main role.
So all three actors started out at only in the ensemble and an understudy, but eventually moved up to a lead role. So it is important to respect them even before they were a lead role. Those three are strong examples of why. They had the talent to become the characters they eventually became.