P.S. (Addendum) If you have shaky hands issues, or real poor eyesight, or whatever that stops you from dripping correctly, don't drip. I don't miss (ok, maybe a drop every 3 days or so... but it's rare). They don't leak either (or crack, or have filler to wash out, or....). Dang near 100% of the juice goes into the vape. IDK what you guys are talking about, other than you're being totally uncoordinated while dripping.
Put the tip of the bottle in the hole, move up a mm or two, drip 3 drops. No miss. No mess. NO WASTE.
And melloyello, I suppose it depends on the carto, but yeah as a general rule, there's more waste over time with cartos. You don't have to be sorry about it

The waste usually comes in if you clean them out, or they die. More so with those that use filler than with wick ones, assuming you can drain the juice to clean/toss.
OP: The experimentation thing is the best. We can only guess/debate. What works best FOR YOU is what matters. Only you can tell.