In reloading.
I said blocking strait of Hormuz is Iran's the last option. They don't have to do that before they try other options. But they are capable of blocking the strait. US Navy already showed they had difficulty to reload in fighting Houthis. Iran is 1000 times stronger than sandal wearing Houthis fighters.
Link: https://www.businessinsider.com/us-navy-stuck-red-sea-battle-cant-fight-houthis-forever-2024-6#:~:text=The%20Houthis%20have%20struck%20multiple,and%20tear%20to%20its%20warships.