I think it is more malicious then that on the manufacturers part. It is more that when something goes wrong it just gives a cryptic error message and the workers have no clue what went wrong and so don't know what to do to fix it or stop it from happening again. For instance, it seems one issue is that if you overfill the hopper and out it through a (4 hour long) cleaning cycle it will fail to reach the required temp and then refuse to work until it has gone through the cycle (for safety reasons). But all it spits out is a cryptic error message and the workers are clueless as to what is wrong. Then they need to call out a technician to diagnose and fix it at a fairly high hourly cost, even though it is something the works could solve if they know what was wrong (ie not filling up the hopper so much).

https://www.youtube.com/watch?v=SrDEtSlqJC4 goes into a deep dive of the problem. And note that the problem is only with McDonalds ones - other chain using the same basic machine don't have the same issues. Likely due to some old partnership between the manufacturer and McDonald screwing over the franchise owners.