OPPORTUNITY.

He who bends to himself a joy
Does the winged life destroy;
But he who kisses the joy as it flies
Lives in eternity's sunrise.

If you trap the moment before it's ripe,
The tears of repentance you'll certainly wipe;
But if once you let the ripe moment go
You can never wipe off the tears of woe.

What is the meaning 'if you trap the moment before it's ripe the tears of repentance you'll certainly wipe but if once you let the ripe moment go you can never wipe off the tears of woe' ?