Most of my emergency jobs over the last three years could have been avoided: hacked sites, broken updates, accidentally deleted content, hosting problems without a backup.
In every one of these cases the cause was the same: no systematic maintenance. What would have cost 50 to 200 euros per month turned, in an emergency, into 1500 to 8000 euros of work, plus reputational damage, plus stress.
Maintenance is not an add-on. It is part of the architecture.