In other countries there is like the main bus system you take and there is another that take you to the main stops

This is the coverage vs. capacity trade-off.

Buses running between full on stations are faster than buses that comprise the network edges. Because the core of the network is focused on capacity. Buses that meander around to provide coverage, minimize walking, and stop every other block are really slow. Like 6 MPH end to end, no faster than riding a bicycle! Do we want a bus network to compete with walking/biking or with driving downtown?