A technically correct automation with poorly written emails still fails. A few concrete, testable principles:

• Subject lines: specific beats vague (“Your cart’s about to expire — 10% off if you finish now” beats “Don’t forget your cart!”).
• One clear call-to-action per email — an email with 5 competing buttons converts worse than one with a single obvious next step.
• Send from a real name, not a no-reply address — “Ada from [Your Store]” gets better open rates than “noreply@yourstore.com” and looks less like the spam it might otherwise be filtered as.
• Test your subject lines — most tools support simple A/B testing on a portion of your list before sending the winner to everyone else.