Many factors will influence your decision to operate as a sole trader or another business structure, such as a company. Your personal life circumstances, as well as your type of business, will have a bearing on which structure is right for you.
All the different types of business structure will have strengths and weaknesses in regards to tax minimisation and asset protection, among other things. The key here is to match these up with your personal circumstances and long-term goals to get the right fit.