Trickle Down Food Chain Contracting
You need to know who is actually doing the work. the above scenario the person who loses out at the end of A large group wins a job and they dont have the capability to do parts of the work. They bid low to win the work. They dont make it clear that they cant do some aspects of the work and will be contracting it out. They then send out enquiries for subcontractors to do the work. Once again the lowest contractor wins the work. this contractor can then subcontract a part of the work which now means there are multiple layers and communication complexity. The contractor at the bottom of the food chain cant make any money and gets beaten up by the prime contractor.
For any project there is always a balance between price, quality and schedule. For the lowest price the other two must suffer. At the end of the day the person who loses out is the Client who wants the work done professionally and a project that is operable and maintainable.