It's a good move if you think you can do things better alone than with your team. And that includes sales/marketing, design, testing, finances, legal & contracts. It's good if you feel there's a lot of inefficiencies and busywork in the office, like commuting or meetings.

It's good if you feel you're underpaid, like if you're the only one building a 3 million dollar app and handling customer service and they pay you $2000/week with few benefits. Your salary as a freelancer will be roughly equal to the amount of wealth you create, minus some economies of scale.

It helps to outsource some of these things at first - get a lawyer, team up with a designer, work with a group like Toptal to help you do marketing. But the easier path is also more competitive, and you can get ahead quite a bit by learning to market yourself.