“…the average person treats a price ending in .99 as if it were 15 to 20 cents lower.”
The tendency is called left-digit bias, when the leftmost digit of a number disproportionately influences decision-making. In this case, even though the real difference is only a penny, research shows that, to the average person, $4.99 seems 15 to 20 cents cheaper than $5.00 – which results in selling 3 to 5 percent more units than at a price of $5.00"
That sounds a lot like when people say, “I’m not affected by advertising at all”. I am sure the effect has influenced some of the purchases in your life.
And even if you are 100% immune to it my point is about selling items to other people. You’re trying to get other people to buy the item you have for sale. Your brain rounding up does not allow you to take advantage of the well-known left digit bias which affects everyone in the world except you. So, if you round up when you sell an item you lose some advantage.
I’m not shitting on your post, it was very interesting! If / whenever I need to sell a product, I’ll think about it.
Fair enough. Upvoted!