The Board of Governors, the highest decision-making body of the IMF, consists of one governor and one alternate governor for each member country. The governor is appointed by the member country and is usually the minister of finance or the governor of the central bank. All powers of the IMF are vested in the Board of Governors. The Board of Governors may delegate to the Executive Board all except certain reserved powers. The Board of Governors normally meets once a year.
The table below shows quota and voting shares for IMF members. Following the entry into force of the Board Reform Amendment on January 26, 2016, members who have consented to their quota increases can pay their quota increases under the 14th General Review of Quotas. Quota and voting shares will change as members pay their quota increases. During this process, this table will be updated regularly (see here for more details on the Quota and Governance reforms agreed in 2010.)
The bolded part seems to suggest the vote increase only happens if the Board approves it, but why does the Board have to approve it, and why don't they let countries increase their vote shares by injecting money into the institution? Is there an official reason for this? It seems undemocratic to me.