Sometimes funding is necessary to grow income enough to sustain the business or hire more engineers or whatever you want to do.
If it costs $40 to acquire a new customer, and you expect a customer to stick around for long enough to spend $90 then it's totally worth doing that, but you need $40 now to make 90$ over some period of time.
If it costs $40 to acquire a new customer, and you expect a customer to stick around for long enough to spend $90 then it's totally worth doing that, but you need $40 now to make 90$ over some period of time.