If the largest empire of your time said give us your land while they had a spear at your throat, you would probably squeak an almost inaudible yes, Greece had other plans, the small city-states of Greece banded together and stopped the Persians from taking any of their land for a long-term period of time.
The battle of Marathon was an astonishing victory for the Greeks, Persia was landing in the town of Marathon so that they could just walk up to Athens doorstep, but the docks were all broken so they went to a nearby beach and saw a force of 10,000 Athenians waiting for them. The Persians thought it was no big deal, they rushed the beach and the Athenians ran and hid in their small wood forts on top of the hills. The two armies had a stalemate for five days and Persia was getting annoyed, so they decided to just storm Athens by sea, as soon as they loaded up their cavalry, the Athenians attacked. They delivered such a crushing blow that the Persians were forced to retreat. The Persians lost a whopping 6,400 men, whereas Athens lost only 192 soldiers.
The battle of Salamis was after Thermopylae, at Thermopylae the Greeks were betrayed by a local shepherd, the Greeks lost 2,000 soldiers and king Leonidas. The Persians were heading to the Hellespont to deliver the final crushing blow to Greece, but they ran into the Resistance in the straits of Salamis. The Persians had so many ships that they couldn’t maneuver well, or get clear shots. Nearly all of the fleet was sunk or sinking, the king called a retreat and they booked it back home.
In conclusion, Persia then just stayed on the sidelines, unless they were certain they could win, this definitely saved them during the Peloponnesian Wars, and until Macedon invaded them, nobody really messed with them, it like the saying “ don’t poke a sleeping bear, unless you are ready for a trip to the E.R.”.