Japanese grammar "てある” [duplicate]

Question

So I just encountered the grammar "te aru" and according to Japanesetest4you it means that something has been done. They provide the following sentence as an example:

君の靴下も全部洗濯してある。
Kimi no kutsushita mo zenbu sentaku shite aru.
'All your socks have also been washed.'

Would it be wrong of me to just say:

君の靴下も全部洗濯した。
Kimi no kutsushita mo zenbu sentaku shita.

Would there be a big difference in meaning?

Answer 1

The difference is like the difference between "they have been washed" and "(someone) washed them".

君{きみ}の靴下{くつした}も全部{ぜんぶ}洗濯{せんたく}してある

• All of your socks have also been washed

• Your socks have all been washed as well

君の靴下も全部洗濯した

• (I have) washed all of your socks as well

• (She has) washed all of your socks as well

• (He has) washed all of your socks as well