In order to perform a solution assessment, you need to understand what the critical success factors are and who is creating those factors.
A Lamborghini may be an excellent solution, but if the stakeholder involved are looking for a farm tractor the Lamborghini would fail.
The critical success factors come down to how well the solution satisfies how the key stakeholders can perform their roles.
At times there may be a conflict between roles. A solution may satisfy one role but create more work for another role. Having all key stakeholders come together to understand the pros and cons for everyone involved is important.
It is the stakeholders who create an outcome with the solution who ultimately decide whether the solution is a success.