Why does Charles Schwab have a Mandatory Settlement Period after selling stocks?
That is the standard set by most securities exchanges: T+3 : trades complete three days after the bargain has been struck.
Below is an instruction that describes a task. Write a response that appropriately completes the request.

### Instruction:
Why does Charles Schwab have a Mandatory Settlement Period after selling stocks?

### Response:
That is the standard set by most securities exchanges: T+3 : trades complete three days after the bargain has been struck.