I have applied to YC with multiple ideas in the past and have been rejected without interview. In my current iteration what I have going against me - solo founder, late 40s, building in a crowded consumer space.

I have no idea what YC looks for and it doesn't matter. I will still apply last minute. Almost all my past applications helped me refine and rethink about my ideas.

It is highly discouraging to hear a reject but that's the life of a founder.