A good consultant should be prepared for risks. Risks can come from expected sources or they can be completely unforeseen. The risks can also be categorized as technical risks or functional risks.

The unforeseen risks are difficult to predict and the best remedy is to identify them early. The other risks can be anticipated much earlier (in fact, some can be looked at before you even start the project). The key to risk management is early identification.

Consultants during the course of implementation  get visibility to the perceived risk. Time delay is one for the frequent reasons of risk and can hit project's success in multiple ways (time, cost escalations, and loss of opportunity). Timely reviews can easily help identify this risk at an early stage.

Low adoption is something which can occur only after implementation, but this too can be identified early if the consultant can understand the end user better.

Unclean data is hard to predict initially, but in a disciplined organization, the risk of this happening is rare. This risk can be perceived during the data extraction and modeling phase.

Technical issues too are hard to perceive early. However, some of them can be identified early, like connectivity to a non standard data source. There can be some issues which crop up after the system goes live. The other technical issues can be performance related, which can come as a surprise.

Changes in the scope of work is one reason for project delays and if not handled properly can become a big risk. A consultant must be aware of all potential risks, and in fact take all possible precautionary measures in advance.