The phrase "penny wise, pound foolish" describes a person who makes wise decisions with smaller sums of money but loses or wastes larger sums of money on dumb decisions with larger sums. It draws attention to how naive it is to prioritize modest savings above large expenses. 

For instance, someone could spend hours seeking tiny deals or less expensive goods while ignoring long term expenses, upkeep, or quality, all of which could result in a larger overall financial savings. This kind of thinking can result in missed benefits, inefficiencies, and financial losses. 

It acts as a reminder to strike a balance between strategic thinking and thrifty living, making sure that cost cutting doesn't compromise overall financial well being. In the end, it comes down to understanding where savings are actually important without compromising the wider picture.