For instance, companies usually issue preferred shares at $25 and redeem them at the same price if they are ever called away. During that time you are paid interest. If the company goes under, bond holders get paid first, then preferreds, then common stock holders. How often are the preferreds paid back in full in bankruptcy (the full $25 per share in this example)?
Traditional preferred stocks pay a dividend though sometimes there's a small interest component. Most are issued at $25 with a 5 year call provision. If it's a cumulative preferred stock and dividends are suspended, any dividend payments missed are owed and must be paid out to cumulative preferred shareholders first if dividends are resumed. If non cumulative, no such obligation exists.
If the company goes under, preferred stocks are wiped out because the company is insolvent. If it survives bankruptcy, preferred shareholders are NEVER "paid back in full in bankruptcy (the full $25 per share in this example)" because $25 is the market price and is not the issuer's responsibility. Share price will be whatever the market deems a share to be worth. The company only has the obligation to pay $25 if it calls the issue and that will rarely happen if the issue is trading for less than $25.