Genesis EP-330 lighting question... Issue with gas flow?

So I have an EP-330 and for at least 2 years now I have noticed that it NEVER lights on the first try if I close the gas valve after the last cooking...
Process is this.
1. Open tank valve all the way (I have tried 3/4 open and different tanks)
2. Turn any burner on high
3. push ignition button...it sparks...I can hear it..
Grill doesn't light.
4. Shut off burner.
5. Close gas valve tight.
6. Open gas valve
7. Turn burner on high.
8. Push igniter...grill lights.

It will light on the first try if I open the valve, turn on the gas, turn off the gas, close the valve, open the valve, turn on the gas, light...every time...

Is this some sort of an issue beyond just the annoyance it is to me?

Do you shut the main gas valve off prior to or after shutting off the burners? If prior to that is your issue. Proper way (if you're anal about shutting the main valve which I am not) is turn off the burners then shut off the main valve. To start turn on main valve SLOOOOOWLY, wait maybe 20 seconds, then turn on one burner at a time and light. For me the easier way is to just leave the main on. Only once in over 30 years of gas grill ownership did I ever have a failure where that would have been a problem. Others have seen my theory. When your water heater shuts off, your dryer, or any other appliance in your home is off do you go outside and shut your main gas off? No? Same difference IMO

Weber recommends shutting the tank off after the burners are shut off. When ready to light grill, they say to turn tank valve fully open and wait about 60 secs then turn main burner on and light. Then turn on additional burners. This works for me every time and that way, you don't take the chance of possibly turning on a burner valve and having the tank go empty. My wife did that a few times and now with this method, it hasn't happened since. Good Luck.

I'm thinking I'm just not waiting long enough after opening the tank valve before I turn on the burner....I would never leave the tank open...I cover the grill and if someone bumped a burner control knob and filled that grill cover with propane you're looking at a world of hurt when Nanny lights up a cancer stick on the ole' patio...