IMO a bunch of the problem is distress and short-term thinking.
You're not planning for 1, 2, 4 weeks out if you're constantly so stressed you're only thinking about today.
And if you're so overwhelmed you're only thinking about today, you're not noticing that you're spending impulsively 5, 6, 7 times a week, and that it adds up.
That's really been the key thing, the times that I've sat down and tried to talk someone through who was struggling with their financial planning.
They never really internalized doing this sort of planning regularly, for various reasons, and are so stressed by the day to day that they do not spend time thinking about much beyond the immediate, not just in terms of finances, so they're not trying to save for a goal, or a vacation, they're just trying to get through the day and pass out, so that kind of planning and feedback of "oh I need to not do that" just doesn't happen, much less learning to stop and think before buying things.
I don't have great advice on how to use this for better outcomes, though - sometimes, just making the suggestion when asked that they start to do this sort of planning regularly has been massively helpful for people, but I have, a couple times, had people ask for advice, only for it to become clear that they were looking for a rationalization to externalize their problems - that is, any proposal which required they change their behavior was off the table.
(The above, by the way, is also, I think, why there's so much backlash about RTO and similar - a lot of people who had been mindlessly struggling through the day, had time to themselves now, and did some thinking they never had the energy to do before...)
You're not planning for 1, 2, 4 weeks out if you're constantly so stressed you're only thinking about today.
And if you're so overwhelmed you're only thinking about today, you're not noticing that you're spending impulsively 5, 6, 7 times a week, and that it adds up.
That's really been the key thing, the times that I've sat down and tried to talk someone through who was struggling with their financial planning.
They never really internalized doing this sort of planning regularly, for various reasons, and are so stressed by the day to day that they do not spend time thinking about much beyond the immediate, not just in terms of finances, so they're not trying to save for a goal, or a vacation, they're just trying to get through the day and pass out, so that kind of planning and feedback of "oh I need to not do that" just doesn't happen, much less learning to stop and think before buying things.
I don't have great advice on how to use this for better outcomes, though - sometimes, just making the suggestion when asked that they start to do this sort of planning regularly has been massively helpful for people, but I have, a couple times, had people ask for advice, only for it to become clear that they were looking for a rationalization to externalize their problems - that is, any proposal which required they change their behavior was off the table.
(The above, by the way, is also, I think, why there's so much backlash about RTO and similar - a lot of people who had been mindlessly struggling through the day, had time to themselves now, and did some thinking they never had the energy to do before...)