Colorado computer problems

I have read in the news that several governmental agencies have been having problems with computer systems. The motor vehicle department's system has been virtually desxtroyed by viruses, and the wealfare departments new system is almost unusable. It seems to me that there are some very poor computer business practices beeing used since both of these 'problems' should have been managed and dealt with without complete disruption of the involved departments. I wonder why these departments could not fall back on backups. I also wonder why the viruses were not stopped by firewalls and anti-virus programs; and why the new wealfare system was not properly tested before being forlled out (at least use a piolt test). I am missing something in my understanding of what happened or the IT people involved did not do a very good job.