Wrangler Men's 5 Star Straight Fit Jeans with Flex

Good fit for me: Dad bod, thick thighs, decent waist. Only complaint is with Walmart, not the jeans: The description says the fabric is 99/1% stretch. Actual blend is 85/13/2 which I prefer as it's a little stretchier.

I picked this size because when I got a dark jeans then the first one first one was lighter blue because when I bought dark blue jeans first time was three size smaller than the light blue jeans so I went three sizes above the light blue jeans and it's too loose but why is it when I bought the light blue jeans in the first time of the dark blue jeans the exact same size the dark blue jeans you hold it up to each other with the light blue jeans there's three sizes too small why was it please let me know thank you