Which is “worthy” of what?

The passage below is from a book, Justice, what’s the right thing to do.

http://books.google.co.kr/books?id=SKEeHVwT5UMC&pg=PA43&lpg=PA43&dq=%22But+company+executives+had+conducted+a+cost-benefit+analysis+and+determined+that+the+benefits+of+fixing+it%22&source=bl&ots=vZjV9debnl&sig=TfLsV5m5tvoaUfMsadoyWy7Zdas&hl=en&sa=X&ei=XhfFUYPyCsyBkwXVwIGQBw&ved=0CCYQ6AEwAA#v=onepage&q=%22But%20company%20executives%20had%20conducted%20a%20cost-benefit%20analysis%20and%20determined%20that%20the%20benefits%20of%20fixing%20it%22&f=false

But company executives had conducted a cost-benefit analysis and determined that the benefits of fixing it (in lives saved and injuries prevented) were not worth the eleven dollars per car it would have cost to equip each car with a device that would have made the gas tank safer. ...It added to these amounts the number and value of the Pintos likely to go up in flames, and calculated that the overall benefit of the safety improvement would be $49.5 million. But the cost of adding an $11 device to 12.5 million vehicles would be $137.5 million. So the company concluded that the cost of fixing the fuel tank was not worth the benefits of a safer car.

In the above paragraph, the red-toned part seems to show a contradiction of meaning. In the former it says “the benefits” were not worth “the cost,” and in the latter it says “the cost” was not worth “the benefit.”

When I look up ‘Webster’s advanced leaner’s dictionary,’ there’s an example sentence as follows:

? This contract isn't worth the paper it's written/printed on.

The example sentence implies that the value of “the paper” is greater that “this contract.” If ‘worth’ is only used in the way of the example sentence. It seems that the latter part of the above paragraph is wrong, so we should change the subject with the object, that is, “the benefits of a safer car were not worth the cost of fixing the fuel tank.”

What do you think of my line of thought?