I can't believe Deb says 20-30% of bags are lost to dunking, unless she is dunking newer, lined bags. I've never lost a bag to dunking and I've only known of a few that have been lost on the forum. And it depends on how to define lost. Some people have ruined bags by dunking because there was a large amount of ink that spread to the exterior. They aren't exactly lost, just not necessarily improved. The only truly lost bags were those that were a lost cause already - the leather had rotted so much that putting them in water caused them to disintegrate. I've only heard of that once or twice. I've seen a few bags listed for sale that look like they would disintegrate too, but it's pretty obvious.
If you only dunk unlined vintage classic bags, you shouldn't have a problem. These bags are almost always improved by dunking, as long as you do it correctly and use plenty of conditioner promptly. You can also dunk some lined bags, like Sonomas, with success.
You are never going to find 100% agreement on the Internet.
To lose 20 to 30% of bags to dunking seems high, but I am basing that on what I have dunked, which has to be easily 4 dozen, over the last 8 years. And at least a dozen went through multiple dunks. Also the bags I have dunked are from the 80’s, 90’s and some 00’s. I would be less inclined to dunk a bag with cracked leather or leather that was really gone. Or a lot, not all bags, prior the late 70’s.
Yes, what was the context for
lost?
I try to choose bags, and I seem to have a bit of success here, that are quite worn, but have really improved with a combination of different products, my special sauce

following the hydration of a dunk. I always go back to the amazing (baseball) gloved tanned leather that inspired Miles Cahn, if iirc, of Coach history. And this is because too, I watched my brothers leave baseballs gloves outside that got soaked in a storm, put in a garage for the winter and then the ritual of my dad and them “oiling” them every spring.
This thread is chock full of success stories of all kinds as well as outcomes that were not satisfying. My concern is for newbies that may come here, or lurk that have unrealistic expectations for issues related to a bag. This may be unpopular but I don’t think all issues can be improved with only general cleaning and conditioning and hydrating vintage Coach bags may cause spots to emerge. And yes, I have seen sentiment on thr net to not use any type of dye, pigment, paint to improve a bag. I am pretty much live and let live regarding what people want to do for bags here or not.
Thank you to the good people here

of this thread!
First, thank you everyone for your advice. This forum has been really educational.
I've noticed verdigris on coach bags before but until reading through this forum I didn't know that was the word for it. I have a question about verdigris: is it harmful to the bag if verdigris remains on it? For example, under the zipper. Is it necessary to remove it?
Do you mean transferred onto the leather? And staining it? Maybe show a pic?