the rule explicit-length-check should be used in comparisons only.
and not be used in other situations such as assigning a variable like this:

 let x =  options.length || 500

and this:

something( options.length || 500 )

also it should be linted only if attached to a string like this

function example( text: string, array: Array<any>){
// .length here is a prototype of string
  text.length

 // but here is a property of an array
  array.length
}