That $10k deposit appeared from nowhere. You didn't 'put the deposit in', and it wasn't transferred from another customer or another bank. And the bank does not need to have $10k sourced from somewhere else.

This is not correct. A bank lends against its cash assets, not against nothing.

Bank accounting works like so: when you deposit $1 at the bank, the bank’s assets increase by $1 (the $1 you just gave it), and its liabilities also increase by $1 (the bank owes you your dollar back when you want it). A bank’s loans are financed by its assets; each dollar it lends is a dollar taken from the asset side of its balance sheet. When a bank lends you $1, it (1) decrements its asset balance by $1, (2) increments your bank account by $1, (3) creates a new asset representing a $1 loan on its own balance sheet, and (4) creates a new liability for you representing a loan of $1 owed.

Point is, a bank does not create money from absolutely nothing when making loans in the way you describe. All loans are financed by the bank’s assets, and a bank cannot originate a larger value of loans than the value of its cash assets. Bank “money-creation” refers to the fact that the total bank account balances in the economy increase when a bank makes a loan; this happens after what I described in the previous paragraph, since the $1 loan now increments your bank account, while nobody else’s bank account balance decreases.

(To see how this works in more detail, imagine the process begins with Alice depositing a one-dollar bill at the bank, and then the bank loaning Bob one dollar. Keep track of the distinction between who has the one-dollar bill and who has a one-dollar bank account balance. The loan proceeds as follows: first the bank gives Bob the one-dollar bill it took from Alice as a deposit, then Bob turns right around and deposits the one-dollar bill back at the bank. The result is that Alice and Bob now both have $1 bank account balances after the loan is made, whereas only Alice did before; the bank still has the one-dollar bill. Summing either bank account balances alone or balances plus dollar bills shows $1 more after the loan was made.)