Seven archetypes recur: structural decline, the over-levered refinancing story, accounting and earnings quality, the broken growth story, the capital-cycle bust, the fad or single-product name, and the serial acquirer. Each has a signature in the numbers and, more importantly, something that forces the move — a refinancing, a covenant test, a restatement, a de-rating, or new capacity arriving on a public schedule.
Before entering, price the mechanics: borrow availability and fee, the dividend you will owe the lender, short interest as a share of float and days to cover, the squeeze fuel of a small float or heavy call open interest, and the equity-issuance defence — companies you are short can and do sell stock into strength to survive.
Because the payoff is inverted and the carry is negative, the fundamental work and the trade structure are separate decisions. Shorts die three ways: too early, too crowded, or rescued. Write down which is most likely for your specific idea before you enter.
Educational, not investment advice.