go through the mill

verb — 2 senses

verb

Idiomatic To experience the suffering or discipline necessary to bring one to a certain degree of knowledge or skill, or to a certain mental state.

UK, Obsolete, Slang To go through bankruptcy.

All know the high estimation debtors held the Act 1861, by the number who went "through the mill" at the close of 1869.1877, The Accountant, volume 3, page 3:

Entry derived from the Wiktionary, under licence CC BY-SA 4.0 — list of authors.