It might be harness or prompting style. Personally I use opencode and my prompting style is very plain and terse . Where tasks are very small. Opus and Sonet too often are too verbose and go tangent. Where GPT5.5 is much stricter.
Generally why build your own CRM? ERP and other resource planning systems I get becouse you can tailor made those to your back office. But for CRM you need mostly reliability.
Difference is pretty big if it’s icy like breaking 100 meters vs 10 meters. Especially if there’s wildlife like reindeers/moose’s you are going to do emergency breathing semi regularly.
It’s more about operational resilience and serving customers than product development. If you run early WhatsApp like organisation just 1 person leaving can create awful problems. Same for serving customers especially big clients need all kinds of reports and resources that skeleton organisation can not provide.
When you ship it is arts and crafts which usually leans heavily to a small group of people Then if you want it to be commercial succesfully it needs some manufacturing practices because otherwise, you end up with legacy software.
If end-users do like it upper managment notices it but it will take time, generally you iterate faster against upper managnent. Same kinda applies when end users dont like that stuff so you cannot lean too heavily to opticks game.