Capital One is an odd example of this. I have read many reviews that state that after 18 months with stellar payment history and carrying no balance that users were told they qualified for an unsecured card but would first have to close the secured card (In order to get the deposit refunded) - or you can keep the secured card and open the new unsecured card as well. A few people indicated they were able to graduate without changing the card and it was converted for them - but 95% of reviews speak to how difficult it is to get deposits back - even from them.
With poor credit, you may not be able to get approved for new credit products like credit cards. Although you may still be able to take out an auto loan or a mortgage, you’ll pay a much higher interest rate because of your low credit score. Compared to a borrower with good credit, someone with poor credit can pay $50,000 more in interest on a mortgage. Over an entire lifetime, you could end up paying over $200,000 more in unnecessary interest just because of bad credit.