Duverger’s curse  

About Duverger’s Law:

• Duverger’s Law, theorized by French sociologist Maurice Duverger, states that single-ballot plurality-rule elections (such as first-past-the-post) structured within single-member districts tend to favour a two-party system.
• In the first-past-the-post system, the candidate winning the highest vote share in a constituency becomes the winner. And the electorates often choose candidates who are most likely to win.
• This mentality of the voters certainly affects the prospect of the third party/alliance.
• Stanford political scientist Gary W. Cox modernised Duverger’s Law and made it more operational in his 2002 book titled Making Votes Count .
• Duverger’s Law is criticised by some experts as the first-past-the-post system of voting has no tendency to produce two-party politics outside the U.S.
• In fact, India is often regarded as an exception to this law at the national level, but not at the district level.

https://www.thehindu.com/todays-paper/tp-opinion/duvergers-curse/article33805841.ece