Opportunities have deadlines even when nobody tells you the date.

Some windows close without any announcement. The person who could have introduced you changes jobs, the program stops taking applications from your age group, the friend who would have started it with you commits to something else. Nothing looks urgent while a window is open, which is exactly why so much gets missed by default.

Look at the thing you have been meaning to do for over a year and ask what would have to change for it to stop being possible. Then take the first small step this week. Usually that step is one message.