It has to be a BIG name to deserve entrance applause. Preferably if the actor is returning to the stage after a long absence.
That said...I am always more disgusted by applause at the end of a performance that somehow manages to morph into "clap along to an invisible beat". You are supposed to be applauding the performers as they take their bows, not turning it into a damn audience clap along.
"My dreams, watching me said, one to the other...this life has let us down."