Reason to incorporate
Incorporate or not to incorporate is a question of limiting the liability of the business to the assets of that particular business. In that sense if your business is sued your personal assets are protected from being seized in order to satisfy a judgement in case the litigation is lost.
I would like to refer you to two of my articles on the topic of limited liability:
1) What Is Limited Liability and Why It Is Important? - here you would learn about the merits of limiting your business liability,
2) How to Avoid "Piercing the Corporate Veil" - here you would learn on how to make sure your company's limited liability ("Corporate Veil") is maintained correctly.
I hope that answers your question,