The personal hard cap guarantees that everybody who want to participate in ICO will participate. Now they are checking the white list and see how many people want to participate in ICO
If to argue logically then it can not be a guarantee since under the condition of a huge number of those who want to buy tokens, in any case, there will not be enough for everyone.
Remember that in this ICO it is obligatory verification of all users. It is imporcible to create 2 accounts just to buy more tokens. If people want to buy more tokens it can buy them on exchangers after ICO.