If you’re not thinking about Delaware, then maybe. Sometimes you’re going to have to. If, for example, you’re forming an LLC for investment real estate, with a few exceptions, that state will require you to form your LLC in the state where the property is. There may be other reasons to be in another state, but those come up rarely.
I wish the answer to this were more existential, and thus more interesting. Alas, it’s as simple as this: when you duly file Articles of Incorporation, also know as charter documents, with the state official authorized to recognize and process such filings. In California, it’s the Secretary of State. In Delaware, it’s the Division of Corporations. Same for LLCs, except it tends to be called Articles of Organization.
Corporations provide liability protection for its owners, as well as its officers and directors, with some exceptions. So, there’s that. Insurance covers some things, not all things. And sometimes a corporation won’t help you . . . for example, if you’re a lawyer and you commit malpractice. That’s on you, individually – corporation or not. Tax may also drive a reason to incorporate or organize an LLC.
Should you? Probably not. Are you required to? Maybe. It depends on the type of profession you’re in. Lawyers, for example, are required to be in professional corporations (“PC”). Forming as a PC may require additional restrictions in your bylaws, for example concerning ownership. So if you don’t need to, generally you shouldn’t. But you may not have a choice.