A bigger monthly cheque later only wins if you live long enough to collect it.
Smaller monthly payment, but it starts right away.
Bigger monthly payment, but nothing arrives for 5 more years.
Each month of delay adds 0.6% to your payment. Wait the full 5 years, and it's 36% higher for the rest of your life.
The early claimer has a 5-year head start in the bank. The delayed claimer is starting from zero, just with bigger deposits ahead.
The early claimer's total leads for years. The delayed claimer's bigger deposits slowly close the gap, and overtake it at the breakeven age.
Claiming at 65 collected more, total.
Delaying to 70 ends up ahead.