you save more bucks on product-creation-or-substitution than service ... let's call it "leverage"
cooking food is a good example, on average you can have leverage up to 10x over dining
generic drug is another, 2-50x leverage over branded one
chemistry ... up to 10000x -- i invested $3 for a kg of washing soda and citric acid (many use weaker base like baking soda and weaker acid like vinegar) which could last me a lifetime. now i rarely go to personal care (shampoo, soap, toothpaste) while at grocery
imagination ... up to infinity (free) -- coding, writing, entertain oneself, etc
changing oil is "service" ... as such, the leverage is low, 5x top
many say it's better to buy than make since you have to spend time making it yourself ... they conveniently forget that they too have to waste time buying (going to seller, making selection, putting order, waiting, paying, reordering)
cooking food is a good example, on average you can have leverage up to 10x over dining
generic drug is another, 2-50x leverage over branded one
chemistry ... up to 10000x -- i invested $3 for a kg of washing soda and citric acid (many use weaker base like baking soda and weaker acid like vinegar) which could last me a lifetime. now i rarely go to personal care (shampoo, soap, toothpaste) while at grocery
imagination ... up to infinity (free) -- coding, writing, entertain oneself, etc
changing oil is "service" ... as such, the leverage is low, 5x top
many say it's better to buy than make since you have to spend time making it yourself ... they conveniently forget that they too have to waste time buying (going to seller, making selection, putting order, waiting, paying, reordering)