So it didn’t work out the way you expected, hoped for, planned.
You now have choices before you.
One option: You can point to all the reasons it wasn’t your fault, all the factors that were beyond your control. These reasons are true, so you are not lying to yourself. (But do be aware that along this route, you could be snared by resentment or hopelessness.)
Another option: You can point to everything that was in your control, but that you did not execute successfully. This option is harder to swallow, but potentially more encouraging because you can do something about it. (Just make sure the reasons are true. Otherwise, you may turn personal responsibility into self-flagellation.)
And here’s the surprise: You can make both choices at the exact same time.
Identify each correctly and you’ll be wiser and stronger, so that next time, you have greater chances of success.
When things don’t work out, when you don’t get picked for the team, when your plans don’t land, don’t let the disappointment be wasted.