Itsy Bitsy Spider

The eensy weensy spider
Crawled up the water spout
Down came the rain
And washed the spider out
Out came the sun
And dried up all the rain
And the eensy weensy spider
Crawled up the spout again.
New verse:
The itsy-bitsy spider
Stuck out two spinnerets
Out came a web
made-up of tiny threads
Along came the wind
That blew so far away
Where the itsy-bitsy spider found
A brand new place to play!And why do they do this?