user profile properties in central admin vs my settings

1. In central admin i have updated the office property of a particular user. After that i logged in to     SharePoint site with that same user credentials. when i click on my settings option it showed some   properties but the office field was not updated. But on the next day it got updated.

    Why it happened? Is there any timer set? If so how to do please explain.

2. Usually there will be a number of properties we can find for a particular user in user profile properties of central admin. But all these properties are not getting displayed by default inmy- settings of SharePoint site for that user. Please let me know the reason.

Chaitanya