Assume you have a product (x) that you are considering building. If you can get to market quickly, you can maybe grow revenues or whatever.
X will take 48 person-months to complete
48 person months is 48 months with 1 persons
48 person months is 24 months with 2 persons
48 person months is 12 months with 4 persons
etc
When time to market is critical, companies will often choose to "buy time" by paying people to cut the time requirements. The math isn't as linear as I've suggested, but most of the time, for most of the projects, you can increase velocity made good by adding people to a project.
X will take 48 person-months to complete
48 person months is 48 months with 1 persons 48 person months is 24 months with 2 persons 48 person months is 12 months with 4 persons etc
When time to market is critical, companies will often choose to "buy time" by paying people to cut the time requirements. The math isn't as linear as I've suggested, but most of the time, for most of the projects, you can increase velocity made good by adding people to a project.