Let me explain : you're at the supermarket and you see some item in on sale, you take it assuming it's cheaper, but if you did calculate it, you'd have noticed that either the bigger format of the same brand or the home brand of the same format are cheaper by weight ($/lb), despite the offer.
Another example, you've been a customer of your insurance/financial institution for years because you made some calculations and shopping around 10 years ago and they were the cheapest for your needs, but you've just renewed your account/policy with them ever since. The thing is, even the second year, there were cheaper options that you failed to consider (many things change on a year-to-year basis : some rebate become available/expire, your situation changes slightly and you fall in another category, cheaper with one company, more expensive with the next, they all adjust their prices, but one raises it less than yours...), now you've been paying 600 $ / year more for the exact same coverage than the competitor, but you were too lazy to place 5 15-minute calls a year to save that money.
Not counting, and laziness.
Let me explain : you're at the supermarket and you see some item in on sale, you take it assuming it's cheaper, but if you did calculate it, you'd have noticed that either the bigger format of the same brand or the home brand of the same format are cheaper by weight ($/lb), despite the offer.
Another example, you've been a customer of your insurance/financial institution for years because you made some calculations and shopping around 10 years ago and they were the cheapest for your needs, but you've just renewed your account/policy with them ever since. The thing is, even the second year, there were cheaper options that you failed to consider (many things change on a year-to-year basis : some rebate become available/expire, your situation changes slightly and you fall in another category, cheaper with one company, more expensive with the next, they all adjust their prices, but one raises it less than yours...), now you've been paying 600 $ / year more for the exact same coverage than the competitor, but you were too lazy to place 5 15-minute calls a year to save that money.