Some people need to spend 110% on the first category unfortunately.
Also it would be nice to have a slot for investments.
Not necessarily do I agree with the whole article but I think the point is that you Need to be in this 50/30/20 kind of lifestyle.
If you are spending 110% on needs you either need to readjust your needs (obviously if poss.) or change a job. Etc. you definitely won't get out of debt this way.
It's just a model they want to show you.
Also the 20% is savings and I think it's a broad name - you can probably put 10% saving and 10% investments.
It's a pretty general article though.
I would suggest that anyone that is like wheres my money etc. going to? What's my spending habits? ...
... He should keep a log for 3 months of all his income and all his outgoing expenses and hell start to see a pattern, if he sees his income is $4000 and expenses are $5000 he needs to start to readjust his spendings.