When can the "correct" assessment be the wrong assessment? When your competitors are assessed incorrectly.
If your property is assessed at 100% of its current value, but similar real property is assessed at significantly less than current value, this is an inequity. In Ontario, the property taxpayer is entitled to the lower of the correct or the equitable assessment.
While many taxpayers may feel they have a good idea of how much their property is worth, it can be very difficult for most to determine if their assessment is equitable. This type of analysis is part of every review I do.