you pay for more than hardware. $325k in hardware also needs people with expertise to run it, those aren’t cheap. Maintaining reputation also means keeping yo

you pay for more than hardware. $325k in hardware also needs people with expertise to run it, those aren’t cheap. Maintaining reputation also means keeping your IP of blacklists and continuously monitoring the major ones . Spending time debugging delivery issues all of which needs people who costs a lot of money. Also 4 million is list price , at that scale most providers like Mailgun, sendgrid , postmark will give you pretty steep discounts and dedicated account managers and high priority support . In any company every bit of effort spent should be on developing your product, not wasted in trying to do someone else job just as good as them then not selling that skill. AWS exists because Amazon figured they were spending a time and effort managing large scale infra and should be monetized. Even at Amazon.com scale it makes sense to externalize it to a shared service like AWS.