Because of ACH is a complex system the payments via ACH Stripe is a bit complicated.
If the customer for the first time in your shop he doesn’t have a verified Stripe bank account. So he has to verify it first. He places an order the information email will be sent to him. There will be all the information about later verification and payment process.
After this, the customer has to wait for a couple of days for micro withdrawals. But he is free to purchase something while he is waiting for a verification.
The customer received verification microdeposits and is follow the link from the email.
There he fills the payment form again and sees the verification form.
After he has entered the micro deposits from his bank account he is able to purchase everything from your shop!
As you can see this is a bit complicated procedure to pay via ACH Stripe. But after the first verification made your customers can pay directly from their bank accounts!