Because Social Security is in trouble. Around 2034, the Social Security Trust Fund will be exhausted, and benefits will have to be reduced about 23%, by law.
The reason it's in trouble?
It's not disability (SSDI) payments. That's a separate disaster: the disability trust fund is separate, and it's about to be exhausted on its own.
It's not SSI. SSI is administrated by Social Security, but is funded out of general revenue.
And it's NOT because anyone "stole that money". Every dime borrowed from Social Security is accounted for, and it's being paid back. But, it will all be paid back in 2034 -- and then there's nothing left.
OASI (Old Age and Survivor Insurance) is the largest part of Social Security. It's been obvious that it is in trouble for years, but anyone that dares suggest doing something is pilloried. We pretty much lost our opportunity to do it painlessly back in the 90's, and longer we wait, the more painful it will be.
The reason OASI is in trouble is simple demographics and economics: the projections back in the 80's were too optimistic. Add in the automatic CPI increases (started in the 70's), and you have a recipe for disaster.
The Social Security Administration has an entire webpage evaluating various alternatives. The only one that works for the long term is a massive tax increase, or an benefit reduction across the board.
“The reason OASI is in trouble is simple demographics and economics”
A major economic reason is interest rate cuts by Obama Federal Reserve appointees. When the Federal Reserve cuts interest rates, the Social Security trust funds eventually earn less interest income.
It’s too late to save the Disability Trust Fund.