5 Reasons Of Inauspicious Mercury You may be wondering how Mercury becomes weakened or affected in a horoscope. Let’s look at the reasons why Mercury can be weakened: Disrespecting the Goddess Durga and Lord Ganesha might weaken Mercury. When a person acquires money through dishonesty, deception, or unethical ways, Mercury becomes malefic and begins to have bad effects. Individuals who mistreat their sisters, aunts, or maternal aunts may suffer the bad impacts of Mercury. Disrespecting the transgender community can lead to negative consequences from Mercury. People who use tobacco or alcohol may be exposed to the negative effects of mercury.