You've seen them hundreds of times, but you don't know what the strips on towels are for

Is it sewn well – without loose threads or unevenness?

Is it smooth to the touch – without any roughness or hard edges?

If the answer is "yes" to all three questions, you are almost certainly holding a quality product in your hands. The small detail that you have overlooked for years turns out to be the most reliable indicator of quality.