[cotc2001]

Nope not really im afraid - it is quite logical the way it is if you think about it.

say for example you had 1 item left in stock but two people add it to their cart at the same time
the one customer gets to the payment section quicker so during that short time the status of that order is "not finished" so effectivley the item has been taken out of stock which means the 2nd customer can't buy it whilst this proccess is happening.

now because the trigger point is set at either payment has completed or payment has failed , if you can't get to that trigger then it would just stick.

The only way I could ever see it working the way you want would be that there is a timing mechanism in place where say for example after 360 seconds any order that is set to not finished is then reverted back to failed thus putting the item back into stock but that would be one to put to a developer.