It is used when something is not as good as it is said to be.

这句美国式的表达方式，经常用在形容事务并非像其描述所说的那么好的状况。

youdao

Yes, I've been to Chinese restaurant many times in America, but I don't think Chinese food abroad is as good as it is here.

吃过。我在国内去中餐馆吃过多次了，但我认为国外的中餐不会像这里那样好吧。

youdao

"If you can pay all your bills and get three meals on the table," says Mr Zadow, "that's about as good as it is going to get."

“如果你能把所有的帐单付清，再有一日三餐饭吃，”扎多说，“那就应该好得可以了。”

youdao

"Matt is one of my very good friends, so I did it as a friend, but also because I love playing the violin."

VOA: special.2010.06.21

The opposition is between poetry that makes money and poetry that, precisely because it is good poetry as modern poetry defines it, does not.

对立性主要存在于为了赚钱的诗歌和,不为金钱的角度，现代诗歌意义上的,好诗歌之间的分歧。

耶鲁公开课 - 现代诗歌课程节选

However, as you know, we didn't stop at the plum pudding model, which is good, because it's a little goofy, so it's nice to move on from that and move on we did.

我们并没有,停留在李子布丁模型上，虽然它很好,但这个模型有点傻。

麻省理工公开课 - 化学原理课程节选

And even that product, as good as it is, needs to be improved.

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It's as good as it is because of advances in statistical translation.

FORBES: Magazine Article

But as good as it is, Ariane is under pressure.

BBC: Ariane rocket ready to do battle