Why are Muslims a defeated ummah today?

Answer 1

As this is asking for an opinion, you will likely have different views.

Answer 1
The question as posed is awkward and confusing. I understand it as asking "Why are the Muslim-majority countries generally weaker countries and not among the World Powers?"

There are several factors:

Corrupt Rulers and No Infrastructure: Many rulers of Muslim countries are content to deprive their people of modern infrastructure and development. They prefer to hoard the money their people give them to build palaces and repressive armies to protect those palaces. As a result, many of the necessary infrastructural and developmental changes which should have happened never occurred. One of the main results of the corrupt governments has been the instability of many Muslim-majority countries.

Regional Disunity: Muslims have gone to war with each other at numerous times and in numerous places. Nearly every border in the Arab World has played host to a military engagement of some type. The Arab World has never had anything even close to the European Union or the Schengen Border Agreement (forget the Muslim World). (The Arab League and the Organization of Islamic Conference are much more like the United Nations and have no superstate components.) Although Muslims, as individuals, may feel connected across borders, like those between Morocco and Algeria or those between Syria and Lebanon or those between Egypt, Sudan, and Libya, their governments do not.

Anti-Educational: There is a strong and pervasive attitude in many Muslim-majority countries that a Western-style education, seeking a high degree of literacy and scientific knowledge is undesirable. Instead, there is a strong pull towards a religious education. This leads to minimal technological innovation in Muslim-majority countries today. While Muslims make up over 23% of the world population, they have less than 10 Noble Prizes in the Sciences and Maths.

Lack of Human Rights: Most Muslim-majority countries deny their citizens fundamental human rights such as equality before the law, freedom to express their opinions (even if they are unpopular), freedom of assembly, equality for women in education and marriage rights, freedom of movement, an end to the slave trade (in a minority of Muslim countries), and other infringements. Statistics have shown a high-level of correlation between the presence of human rights and economic and political affluence.

Foreign Policy Over Domestic Concerns: Many Muslims are concerned about irrelevant foreign policy issues among Muslims and Non-Muslims in other countries. The Cypriot situation and the Israeli-Palestinian Conflict are wholly irrelevant to Pakistan and Morocco, but people in those countries spend an inordinate amount of time discussing those issues. That time comes out of discussions about what to do about serious problems in those countries such as women's education or the lack of infrastructure. If there is no clamor for these domestic improvements, they will not happen.

Failure to Compromise: Unlike Western Societies which see public debates and elections as a fair mechanism for deciding which opinions should get the Right of Way, many in the Middle East prefer to staunchly advocate their position by whatever means are necessary because they are assured of their correctness (either by God or personal conviction). This means that both domestic and international policy issues that produce gridlock have the potential to erupt in conflict and extreme measures as opposed to a general consensus that people can agree to even if they are not in love with it.

Failure to Permit Ethnic Autonomy: Many ethnic groups in the Muslim world, such as the Kurds, the Balochis, the Darfurians, the Acehnese, etc. find themselves in states run by other ethnicities that deny them the ability to have a strong say in their affairs. Instead of granting them autonomy, like European countries in similar positions have done, they choose to repress them. This has gone on to the point where the only recourse is full-scale revolt.

Tribal Conflicts: Especially in Arab States, there are numerous tribes that have long-standing feuds with one another and threaten to disturb the peace. Creating a national identity is critical for making the state safe enough for domestic commerce.

Lack of Foreign Investment: Due to the frequent instability and the strong Anti-Western sentiment in Muslim-majority countries, foreign companies are not willing to invest in production and infrastructure in Muslim-majority countries and will choose more stable and friendly nearby countries. Sri Lanka and Vietnam have seen much more investment than Pakistan or Egypt for exactly these reasons.