Even if they were singers before, that does not make them better
singers after foraying into acting. It is just that they can now
leverage on the popularity as actors to help kickstart their music
career again.
Tao Zi is a classic example for this case. Starting out as a singer
more than a decade ago, she did not get much success with her
"whiny" voice singing 'wanting to chase after good boys'. Only
after she had made a name from being a host did she get the 2nd
shot at singing. With her popularity now, it brought recognition
and eventually brisk sales of her albums. This would be highly
unlikely to be the case 10 years ago when she was a nobody. Of
course, she had improved much since her maiden effort, but without
her popularity, she will be just another singer out there in the
scene.