When a long-running SIP stops, it is rarely because the investor decided to stop it. Far more often, something administrative broke and nobody was watching.
The mandate outlived the bank account
Salary accounts change with employers. The NACH mandate stays registered against the old account, the debit fails, and after a few consecutive failures the registration is cancelled by the system. No alert, no letter, and the investor discovers it months later.
The registration reached its end date
Many SIPs are registered for a fixed term because a form demanded an end date and something had to be written there. When that date arrives, the instalments simply end. A perpetual registration avoids this and can be stopped any time by instruction.
The balance was short on the debit date
- A debit date set before the salary credit fails almost every month
- Three or more consecutive failures typically cancel the registration
- Some banks levy a charge for each failed mandate presentation
What actually prevents it
Set the debit date a few days after income reliably arrives. Register perpetually rather than for a fixed term. Update the mandate on the day you change banks, not when you next remember. And keep a single list of every running SIP, with the amount and date, somewhere the household can see it.
None of this is sophisticated. It is simply the part of investing that nobody finds interesting enough to check, which is exactly why it fails.
