As long as health care professionals have not warned the individual against doing something, perhaps driving or lifting, then I feel that even if he or she has an illness that is not going to resolve, this is not a reason to stop doing things. Carry on as able.
When we look at the success story of those who do exercise as their habit, we recommend that healthy habit to other groups of people (mostly lazy to do exercise). We've conducting millions of health promotion interventions, mostly successful in some scenarios, but mainly failed in the real life.
"Incidences change a life, and the changes changed"
Now we look at the individual level when someone had a certain disease (s) e.g. CKD, DM, HTN, Cancer ..., they may change to be better or to be worse. Some people have started a new healthy life with many healthy activities, some of them succeeded, some failed; Other groups may commit to bad habits (smoking, drinking, even drug), and get psychological disorders (fear, anxiety, depression), or even commit suicide or revenge.
It is too early to judge people as lazy when he or she failed to change their life. I am one of witness to get surprised to see such lazy persons finally change their life through several years. As if they had found some substantial reason to change their behaviour, that is so-called their motivational switch. Sometimes the news that his close friend got found to have serious cancer may trigger the changes. Death of the colleague, having a grandson, losing their job , and so on. But something that seems to be meaningless could be the reason in some cases.