spam-filter-triggerslisted

# Spam Filter Triggers Modern filters are classifiers trained on behaviour, not keyword lists. The old "never write the word free" advice is mostly folklore, and the sites that score your email out of ten are matching against rules that stopped being decisive years ago. What actually decides placement, in order: ``` 1. Authentication and domain reputation ~60% of the outcome 2. Recipient behaviour — replies, deletions, complaints 3. List quality — bounces, traps, dormant addresses 4. Content and structure ~10% of the outcome ``` So if mail is going to spam, check the first three before rewriting the copy. Content is the smallest lever and the one people reach for first. See `email-deliverability` for the rest. That said, content does matter at the margin, and the margin is where a lot of cold email sits. ## The things that genuinely hurt **Links.** The strongest content signal. A first cold email should have zero links, or one at most. Every link is something to evaluate, and links to unknown domains score badly. - **Never use link shorteners.** bit.ly and similar are heavily associated with spam and obscure the destination. - **Never use a shared tracking domain.** You inherit every other sender's reputation on it. Use a custom one or turn tracking off. - **Don't link a calendar in step one.** Save it for after they reply. - **Check the destination's reputation.** Linking to a domain on a blocklist tanks the message regardless of your own stand