Oh, come on.
All through this thread you've had tipping explained in minute detail to you, and it's also been revealed that tips can provide a very decent living, especially for waiters.
Yet you persist with this anglocentric nonsense and faux bafflement.
As PP says, why should tipping need to be explained in minute detail? It's not peer-reviewing a scientific thesis: it's just receiving what should be a very basic service, one which you may not even need or want, and it being made deliberately obscure as to how much it costs you, because a culture doesn't seem to understand the basic concept of stating a price - an actual price - in order to obtain offered goods or services.
Yes, it has been revealed that waiting staff can make a huge amount of money - but clearly at the expense of giving clear prices to would-be customers - and protests to those who don't tip (or undertip, according to what they are wanting) about how poor waiters are and thus utterly dependent on their tip!! A lot of lawyers and doctors also make massive amounts of money, but at least they state their fees upfront and don't rely on socially compelling customers to pay them significantly over the agreed price by a high amount, for no reason other than that they have done the job they were paid to do, as agreed.
It really does seem to turn things on their head when asking for an agreed price for buying goods and services is called 'nonsense', as opposed to all of the many tipping rules, expectations and experiences that have been recounted on here!
Why is it just Anglocentric, though? Do you see these kind of 'tip everybody for everything' customs throughout Europe - or indeed in most countries of the world? I believe the practice is actually considered insulting in Japan - presumably because the Japanese are skilled in business and setting prices that are fair and transparent to all and also build in wages for the staff. That makes much more sense to me - all these Anglocentric Japanese people, eh?
I realise that people in very poor countries are obviously happy to receive tips from tourists, but this is usually a result of in-built gross inequalities, where a tourist from the West can give the equivalent of a few pence to somebody helping/guiding/serving them and make a big difference to their and their family's life - nothing about a person on minimum wage being socially compelled to hand over extra money to a rich waiter in a wealthy country, so that they can make in an hour what the person in the poor country might struggle to make in a year.