Third pair 511's in 6 month's

I have generally always worn Levi's and prefer it as my go to pair of jeans, I recently discovered the 511 range and purchased a pair around 6 months ago. This pair tore in the front near the zip line just under normal wear. I then went and purchased a new pair and noticed not too long after the jeans had then tore near the back pocket stitching. I am now on my third pair in the space of around 6 months and they have also now tore in the exact same place near the back pocket stitching. These have all just been worn under normal circumstances and I would expect the quality of the jeans to be much higher than this for the price that is being paid for them.