LIA recommends 3.9x annual "income" for CI coverage. Why not 3.9x of annual "expenses" (likewise for ECI as well, though its a different/smaller multiple)?

I asked about LIA study in a previous post:

https://seedly.sg/questions/how-much-coverage-i...

seems to me that the recommendations are dreamt up by someone. if there are any stats or evidence, they are not showing.

You plan your life based on your income, not your expenses. And your income is essentially expenses + savings.

If you only cover your expenses, you won't be saving and investing when you're ill and out of work.

If you cover as per income, your retirement planning and investment planning isn't derailed.