Incredibly high turnover - in the time I was there, at least half of the workforce (that i can remember) were let go or left and then replaced.
Non-existent HR department- quite literally they have no HR.
Constantly overworked - they were bringing in more clients than we could handle, promising things we frankly couldn't deliver.
Management run the business like its a much bigger company than it actually is
For an IT company, it was run by people with very limited IT knowledge, usually leading to us having to clean up their mess as best as we could.
They never liked to let anyone go in person, they usually waited until they were on holiday and then sent them an email.