I’m gonna need you to bear with me here, this will be kind of a long answer but I will bold a few key important things.
Islam does allow the practice of polygamy, however it’s not required nor is it encouraged unless you can treat all of your wives equally. If the man lacks material and moral conditions, or he is not competent enough to satisfy all of them, then he will not be eligible to take more than one wife.
Islam did not introduce polygamy. Among all Eastern nations of antiquity, polygamy was a recognized institution. Among the Hindus, polygamy prevailed from the earliest times. There was, as among the ancient Babylonians, Assyrians, and Persians, no restriction as to the number of wives a man might have. Although Greece and Rome were not polygamous societies, concubinage was a norm. Islam regulated polygamy by limiting the number of wives and bringing responsibility to its practice. In fact, according to David Murray, an anthropologist, historically polygamy is more common than monogamy.
The Muslim scripture, the Quran, is the only known world scripture to explicitly limit polygamy and place strict restrictions upon its practice:
“… marry women of your choice, two or three or four; but if you fear that you shall not be able to deal justly with them, then only one.” (Quran 4:3)
The Quran limited the maximum number of wives to four (this was to restrict the limit and cease men from having affairs outside the sanctity of marriage). In the early days of Islam, those who had more than four wives at the time of embracing Islam were required to divorce the extra wives. Islam further reformed the institution of polygamy by requiring equal treatment to all wives. The Muslim is not permitted to differentiate between his wives in regards to sustenance and expenditures, time, and other obligations of husbands. Islam does not allow a man to marry another woman if he will not be fair in his treatment. Prophet Muhammad forbade discrimination between the wives or between their children. *Polygamy was encouraged during the time of war when many husbands of wives did not come back, and it encouraged men to take wives in order to support and care for the children.
Also, marriage and polygamy in Islam is a matter of mutual consent. No one can force a woman to marry a married man. Islam simply permits polygamy; it neither forces nor requires it. Besides, a woman may stipulate that her husband must not marry any other woman as a second wife in her prenuptial contract. The point that is often misunderstood in the West is that women in other cultures - especially African and Islamic - do not necessarily look at polygamy as a sign of women’s degradation. Consequently, to equate polygamy with degrading women is an ethnocentric judgment of other societies.
Even though we see the clear permissibility of polygamy in Islam, its actual practice is quite rare in many Muslim societies. Some researchers estimate no more than 2% of the married males practice polygamy. Most Muslim men feel they cannot afford the expense of maintaining more than one family. Even those who are financially capable of looking after additional families are often reluctant due to the psychological burdens of handling more than one wife. One can safely say that the number of polygamous marriages in the Muslim world is much less than the number of extramarital affairs in the West.
Please correct me if I said anything wrong.