When your cheap dedicated server goes down and your admin is on holiday and you have hundreds of angry customers calling you, you'll get it.
Or you need to restore your Postgres database and you find out that the backups didn't work.
And finally you have a brilliant idea of hiring a second $150k/year dev ops admin so that at least one is always working and they can check each other's work. Suddenly, you're spending $300k on two dev ops admins alone and the cost savings of using cheaper dedicated servers are completely gone.
Or you need to restore your Postgres database and you find out that the backups didn't work.
And finally you have a brilliant idea of hiring a second $150k/year dev ops admin so that at least one is always working and they can check each other's work. Suddenly, you're spending $300k on two dev ops admins alone and the cost savings of using cheaper dedicated servers are completely gone.