Hang on a minute, after reading the thread, the proper method is to go 'acceptable' weights but high reps? Did I understand correctly?

As a person whom just started out, obviously I cannot lift heavy weight (currently only using LifeFitness machines, unsure whether these are better or free weights are better)

Anywho, I'll use myself as an example (please don't laugh too hard )

For the 'chicken wings' machine (the one for shoulder) I find that with a weightage of 20Kg (44 pounds) I can do 3 sets of 12, perhaps even 15 reps per set before the muscle burn really hits.

Should i increase to 25kg (55 pounds) I can't seem to finish the last set, meaning it would like something like

25kg x 12 times
25kg x 11 times
25kg x 8 times

So are you guys saying it's better to do the former rather than the latter?