The WHILE will loop till the condition you set is true and the user will drop out of the while when the condition is not met anymore. Usually Operand1 and/or Operand2 are variables that will be modified at runtime

For example, you could have such condition:

${MyVariable} greater than 10

Your ${MyVariable} could be a variable extractor or a counter or any other type of variables.

You should check NeoLoad documentation for another example here