There is a summer solar term, why not a cold solar term?

Summer is the end of summer weather. This is the first solar term after beginning of autumn.

The Great Cold is the last of the 24 solar terms. After its end, it is the beginning of reunification, namely beginning of spring, which also represents the gradual warming of the earth; Then solar terms are rain, corresponding to solar terms such as light snow and heavy snow, all representing precipitation. After the rain cleared, the weather turned warm completely.

If you want to set a cold solar term, the better nodes should be beginning of spring and Rain, but beginning of spring can't move. Rain is an important precipitation node, so you can't set a cold solar term.

I am single-minded, please criticize.