When declaring a variable, you should make the scope as tight as possible to conserve memory and minimize runtime errors. For example, do not declare a variable at the class level if it is only used in one procedure.
Tight variable reduces memory usage, improves performance, and makes it more difficult to introduce bugs by referring to a type in the wrong place.
By default, Total .NET Analyzer does not identify constants and controls that can be tightened. You can change this default behavior through the Rule Editor.