The term substitution is from late 14c., "appointment of a subordinate or successor," from Middle French substitution or directly from Late Latin substitutionem (nominative substitutio) "a putting in place of (another)," noun of action from past participle stem of Latin substituere "put in place of another, place under or next to, present, submit," from sub "under."
Substitutes in Porter's model of five forces means the availability of a product the consumer can purchase instead of the industry’s product. A substitute product is a product from another industry that offers similar benefits to the consumer as the product produced by the firms within the industry. An example of a substitute is natural gas instead of petroleum. Butter and margarine. Tea and coffee. Bananas and apples. AI and people. Substitutes are everywhere and becoming more and more accessible.
Appointing success, substituting new problems, arrange solutions