How much selling is too much.
THE RATIO
Mostly useful, occasionally promotional.
The specific proportion matters less than the pattern being clear to the reader.
WHY IT MATTERS
A list that only receives offers stops opening. Then the offers reach nobody, which defeats the purpose.
A list that receives useful content opens habitually, so the occasional offer is seen.
WHAT COUNTS AS USEFUL
Something the reader can act on, learn from, or benefit from without buying.
WHAT COUNTS AS PROMOTIONAL
Anything whose purpose is a sale.
THE MIDDLE GROUND
Genuinely useful content about something you sell. A guide to choosing between options, where you happen to sell them.
That works when it is honest and fails when it is an advertisement in disguise.
WHAT YOU SAID AT SIGNUP
If you promised monthly guidance and occasional offers, honour that.
Subscribers who receive something different from what was described unsubscribe, reasonably.
THE PRACTICAL RULE
If you cannot remember the last time you sent something without an offer in it, the balance is wrong.