Why is this an issue?

The typeof operator returns a string indicating the type of its argument, and the set of returned values is limited:

• "undefined"
• "boolean"
• "number"
• "string"
• "symbol" (since ECMAScript 2015)
• "function"
• "object" (for null and any other object)
• "BigInt" (since ECMAScript 2020)

Compare a typeof expression to anything else, and the result is predefined: false.

Noncompliant code example

function someFunc(x) {
  return typeof x === "Number"; // Noncompliant, function will always return 'false'
}

Compliant solution

function someFunc(x) {
  return typeof x === "number";
}