The term "label drilling" comes froma time when ball labels used to be placed on the ball's CG, with no or little pin distance. To keep the ball legal, the CG was commonly placed in the palm, hence the name.
Today, placing the CG in the palm is stll a valid option, but ball technology (esp. core design) has advanced and old school label layout is a different thing than today - esp. with large pin distances.
Traditionally, the pin is placed in a 45° position from the CG - with (relatively) weak cores like pancakes or low RG diff. cores like the Faball Hammer cores this created (and creates) a smooth, continuous hook with a strong mid lane read and little back end, easy to read and a good beginner option because the ball will hook and you cabn drill a ball label with little regards to a player's PAP - The CG position makes sure the ball remains legal.
With today's much more potent cores and larger pin distances, you can create a VERY strong and early mid lane read - IMHO very suitable for long and oily patterns. But for a player with good hand it can make the ball hook and roll pretty early.
Another drawback of a classic label setup ist the mass bias ending up in the track area. For a high tracker, this CAN (but must not) create a weird flare reaction, e. g. backwards flare or an inconsitent reaction over all.
To sum it up: good beginner option, smooth, controllable hook, arcing ball motion, potential early roll and burnout.