There are lots of reasons why people can't immigrate overseas, some of which are listed below.
1. Lack of sufficient supportive documentation e.g. not enough evidences for sources of funds for some business visa, lack of employment references in the right format.
2. Failure in good character and health checks.
3. Over age limit - There is age limit for the main applicant e.g. 45 for Australia skilled migration, 55 for Australia subclass 188a Business Innovation or 188b Investor visa and age limit for dependent children.
4. Don't have enough points to apply for the visa or to be invited for visa application e.g. the older the main applicant is, the less age points he gets.
5. Not enough time to process the visa application before the policy changes or secure the limited quota - immigration policy always change over time and limited quota is available for the early birds who plan and submit their applications ahead.
6. Failure to manage risks - While your qualified immigration consultant has his responsibility to advice you the risks involved in your visa application, you, the main applicant, has to understand and manage well your risks in terms of time, cost, finance and other factors in order to work along with your immigration consultant to complete your visa application.
7. Have not engaged the right qualified immigration consultant or immigrant attorney to process your visa - Quite a few of my customers told me they have wasted a lot of their time getting no where as the immigrant agent whom they have engaged have not given them the right advice. You are advised to engage an experienced, licensed and qualified immigration consultant or immigration attorney to process your visa, understanding that sometimes paying less means you are getting less quality of service.
8. Failure to provide true and complete information - You are advised to inform your immigration consultant at time of engagement any limitation to provide your true and complete information to avoid failure in your visa application.
John Hu of John Hu Migration Consulting