How complex is your life?
This isn’t an existential question; it’s more about the assets you own and the people you support. Do you own a house? Do you run a business? Are you supporting dependents? Or are you single and free, responsible for nothing and no one? If you said yes to any of the first 3 questions, you might need some help. Itemizing deductions for a kid or a business is difficult. Doing this on your own means reading through pages and pages of forms, to figure out what’s applicable and what’s not. And there’s always the chance you might mess it up. That means the IRS could reject your return, and you’ll have to do it again.
An accountant is an expert in these areas. He or she can tell you what deductions apply and which ones you can forget about. And they’ll make sure your forms are error-free. However, if you have no assets, kids, or businesses, you’re literally entering your W-2 information and you’re done. Stick to doing your taxes yourself.