Yandex limits its liability to 10% of the cost of services under contracts

I quickly looked through the offer for the provision of services by Yandex, for example: the Offer for the provision of Yandex.Direct services , and found the following item:

12.3. The total amount of Yandex liability under the Agreement, including the amount of penalties (fines, penalties) and / or compensable losses, for any claim or claim in respect of the Agreement or its performance, is limited to 10% of the cost of the Services under the Agreement.

In principle, there are no complaints against Yandex, but there are several general questions:
1. Does this clause of the agreement (offer) contradict any provisions of the civil legislation of the Russian Federation?
2. Where did this 10% figure come from? Why Yandex, if it wants to protect itself from potential losses in various disputes and litigations, then will not write down in this offer the figure of 1% or 0% in general?

What is still interesting, earlier (namely, in the editorial offices of the offer until 10.10.2006 inclusive), this paragraph sounded differently, namely:

12.3.The total liability of Yandex under the Offer Agreement, for any claim or claim in respect of the Offer Agreement or its performance, is limited to the amount of payment paid to Yandex by the Advertiser under the Offer Agreement.

However, this clause was changed in the offer of 10/15/2007 , where Yandex actually reduced the ceiling of its liability to 10% of the cost of services under the contract.

PS All historical editions of the offer Yandex. Direct posted here at the bottom.