This is what happens when a company grows amazingly fast but doesn't have a solid infrastructure or experienced management. Every single day felt like a complete crisis. The company is vastly understaffed for the volume of work they are attempting to achieve. Instead of hiring more people or taking on fewer projects, management would make employees pull 60-70 hour work weeks. Employees were all salaried, so they couldn't care less how many hours you were working.
Management had zero respect for employee's personal time. Your personal phone becomes your work phone and you will get phone calls and text messages at all hours of the day every day of the week. I once went on a 30 min walk after I got home one evening, and left my phone at my house. When I returned, I had +40 missed work-related text messages. All my coworkers worked weekends -- 8-10 hours each day on the weekend was not unusual.
There was absolutely no training for newcomers. I understand that sometimes it works best to learn on the job, however if that is the case newcomers need to have a few experienced employees around that they can get tips from. The most experienced person in the department I was working in had been there for 6 months.