Four signals that show it is not worth wasting time on a prospect

It is not worthwhile to invest time in every prospect and try to sell them your product. Either it is a lost cause from the outset and you simply cannot persuade the client with your offer, or the client will not be worthwhile in the long term even if they sign a contract with you. In such cases, these are typically customers who consume too much of your time, resources, finances, and energy to be economically worthwhile. How can you recognize these types of potential clients on whom you should not expend your energy before closing a deal and thus save yourself many complications?