In some shops this is solved by staggering scheduling so people work on several projects. Some aspects of HW can be simulated (think analog with SPICE-likes, or logic level like the chip designers and FPGA users do) so this reduce the need to iterate every time in hardware.
A lot of the iteration work can also be done on the board you received. You don't have to wait for your new board to see if those additional decoupling capacitors will do something, you add them on your current board by hand... You would be amazed at how far rewiring can go, sometimes entire BGAs are removed, installed dead-bug style and each pin wired by hand.
A lot of the iteration work can also be done on the board you received. You don't have to wait for your new board to see if those additional decoupling capacitors will do something, you add them on your current board by hand... You would be amazed at how far rewiring can go, sometimes entire BGAs are removed, installed dead-bug style and each pin wired by hand.