I do believe, that if over used, Penicillin can become less effective.
On minor cuts, I just keep them clean and let them heal.
On larger stuff, I have sutured and stapled, then wipe down with iodine only.
I feel the key is to keep it clean, no matter what you put on it.
Some stuff applied can have adverse reactions, causing an itch or burn, which can make doge chew and pull staples/sutures.
Just my $.02.