Interestingly there is a saying amongst pilots that is: "The second engine flies you to the scene of the accident". I'm not sure if this works as a metaphor in this case.
from http://www.av8n.com/how/htm/multi.html
Q: In an underpowered twin, what is the role of the second engine?
A: It doubles your chance of engine failure, and it will fly you to the scene of the accident.