it sums it very well up. You really need to know what it is you are doing and have more than exceptional industry knowledge to run such a business in 2021. As mentioned already by @Sols, there are only a handful acquiring banks in this world, you will end up with one of them sooner or later if you are in this area of the processing business. It was already like that decades ago.Biggest mistake rookie processors do is take on reckless merchants that rack up tons of chargebacks and then leave you with big fines and penalties, and closed merchant accounts and burned relationships.
Second biggest is working with dodgy processors that run away with money.