The weather is not as good as expected, but you have to fly if you want to go.

The weather is not as expected, but if you want to go, you must fly.

The weather is not very good, not as good as expected, but when it's time to go, we still have to go and fly.

This sentence comes from a lyric in Eason Chan's song "Time is like a Song", which mainly expresses that there are always some things in life that are unpredictable and beyond our control, but we can choose how to deal with them.

Even if we encounter difficulties and challenges, we should still face them bravely and respond positively, because only in this way can we grow and progress.