Not hold a candle to someone

Not hold a candle to someone
Not worthy of tying someone's shoes

Non essere degno di lustrare le scarpe a qualcuno 
Non reggere il confronto
Not worthy of tying someone's shoes

Non essere degno di lustrare le scarpe a qualcuno 
Non reggere il confronto
Meanings
To be far less competent or have far less skills than someone else
Examples
When it comes to performance, Corvette can't hold a candle to Ferrari
In quanto a performance, una Corvette non regge il confronto con una Ferrari
What a difference between the two brothers! One is a war hero and the other is just a little cheat not worthy of tying his brother's shoes
La differenza tra i due fratelli è incredibile: uno è un eroe di guerra e l'altro è solo un imbroglioncello nemmeno degno di lustrargli le scarpeOrigin
Before electric lights, someone performing a task in the dark needed a helper to hold a candle to provide light while the task was performed. Much as a helper might hold a flashlight today. Holding the candle is of course the less challenging role. Someone who is not even qualified to hold the candle is much less competent than the person performing the actual task