How do companies like Arris keep getting work? I have an ISP supplied Arris Cable Modem (luckily not vulnerable) and it is dreadful. The UI is shonky, looking

How do companies like Arris keep getting work? I have an ISP supplied Arris Cable Modem (luckily not vulnerable) and it is dreadful. The UI is shonky, looking at the HTML & CSS underlying it is enough to make you weep, outdated JS libraries, and - seemingly - no software updates. I could just about understand if it was stable and gave good WiFi - but the ISP's forums are full of people complaining about it. All I can assume is that Arris is £1 cheaper than the next model, and the ISP have decided that dealing with customer complaints is cheaper than a higher CapEx.