> why people still use wlog [?] checks instead of going with other methods that they could also choose to use, in 2024.
Anecdotally, I wrote a check to my landlord yesterday, because a few months back they claimed they never got the automatic bill-pay from my bank, and my bank said it was already sent, and weeks later my bank said the recipient refused to take it... Anyway, no party was ever able to tell me why an automated process that worked unattended for months suddenly stopped working for no discernible reason.
All financial infrastructure is a patched-together collection of systems spread across multiple different firms made of multiple suborgs with vastly different levels of observability into and understanding of their local part of the total system. For many routine problems, the cost of having a rigorous answer to “What just happened?” is far, far greater than the dollar amount at stake in the transaction. You’d need the equivalent of a federal agency doing an after-accident investigation to make headway, at the cost of millions.
So we chalk it up to gremlins and move on, for better or worse. (This is one reason why financial institutions have an operational losses budget. Sometimes the gremlins eat someone’s money. So you just charge it to Ops Losses and move on.)
I write checks to my handyman, because he takes either check or Venmo. And Venmo refuses to validate my bank account. I never see the test deposit show up, and on the Venmo side it just says "try again later". So, checks it is. Say what you will about writing checks, but they are reliable in a way that digital payments aren't.
WLOG means "without loss of generality". Originally from mathematics; a proof by division into cases may say something like "assume, without loss of generality, that X is even ..."; WLOG flags a statement that applies just as well to other cases with obvious analogous changes. As generalized to non-mathematical writing, WLOG means "I could make an obvious analogous statement here about similar things for similar reasons".
Bill pay adds several middlemen. Before there was each party’s bank and the postal service. Now there’s the bank’s bill pay department which is sometimes contracted out. The actual printing and mailing of the check is usually contracted out. The bill pay service sometimes tries to be smart about binding an address to a name and sometimes autocorrects to the wrong address. Finally checks always have human error on the part of the two meat bags that are the payer and payee (threw out envelope or let it fall off their table and under a couch).
That's the last-ditch method for making sure they can pay anyone. My bank lets me pay anyone via online bill pay, some of whom have registered with the bank in a manner that allows fast transfers, and some of whom get mailed a check that may take up to 5 days to arrive.
Anecdotally, I wrote a check to my landlord yesterday, because a few months back they claimed they never got the automatic bill-pay from my bank, and my bank said it was already sent, and weeks later my bank said the recipient refused to take it... Anyway, no party was ever able to tell me why an automated process that worked unattended for months suddenly stopped working for no discernible reason.