There was pressure to ignore warnings because President Reagan was scheduled to be present for the launch. 
In higher levels of management, things get more political. Looking good and getting exposure count for a lot. No one wants to be the guy that made nasa look bad by slipping the launch date. 
In tech, most managers tend to be rated by how well their projects meet schedules and how much operating expense they can minimize, since that&#x27;s the only thing their managers have any sense of control over. Your boss doesn&#x27;t want to take the heat for delaying project &quot;glitter unicorn&quot; by a week so you can  fix 2 major security holes in the service, one which allows customers to login without a password. And this is why your company won&#x27;t spend $500 for a data backup system or why it takes 4 months to get your broken keyboard replaced. 
It&#x27;s turtles all the way up.