Seed either comes up or it does not, and when it does not it is rarely obvious whose fault it was. So we do not argue about it.
If a packet fails to germinate, tell us and we will replace it or refund it. No photographs, no forms, no questions about your soil temperature. One reasonable claim per variety per season.
What we ask in return is that you give it a fair go: sown at roughly the right depth, at roughly the right time of year, in something that has not dried out completely. Carrot Chantenay taking three weeks is not a failure — carrots are simply slow, and more carrot seed has been dug up impatiently than ever failed to germinate.
If you are sowing from an old packet and want to know where you stand first, the seed-storing guide explains the ten-seed test. It takes a week and settles the question.