Warren closed unprofitable international operations, switched advertisers, made changes to the board, No independent studies of e Harmony's methods or success rates have been published.
Prospective members complete a proprietary questionnaire about their characteristics, beliefs, values, emotional health and skills.
Satoshi Kanazawa said that part of the success of e Harmony can be explained by the high cost of entry in terms of the amount of time required to answer the initial questionnaire—over 18 hours, although other sources put the time to complete the relationship questionnaire at approximately one hour.
Using Laurence Iannaccone's original idea that success of fundamentalist churches is explained by the high demands imposed on their members, Kanazawa hypothesizes that a similar self-selection mechanism is at work with e Harmony: "they select their members very carefully, and only admit those who are very committed (or desperate; if anyone who chooses to join e Harmony is truly desperate to get married, then it can potentially and partially explain why it produces such a high proportion of all marriages in the US)." Another factor suggested by Dan Ariely is the limited choice of partners offered, which may make the decision easier for some.
When it began, e Harmony did not offer same-sex matches; it now offers them through a separate service, Compatible Partners.
Warren said that he had done extensive research on heterosexual marriage but did not know enough about homosexual relationships to do same-sex match-making, which he said "calls for some very careful thinking. But at the same time, I take a real strong stand against same-sex marriage, anywhere that I can comment on it." Theodore B.
In 2010, e Harmony settled a separate class-action lawsuit filed in California that alleged illegal discrimination based on sexual orientation.Matching algorithms, which the company believes matches people's core traits and values to replicate the traits of happy couples, use these answers to match members with users the company believes will be compatible.Starting in January 2017, e Harmony users could see why they are considered compatible with a feature called "The Two Of You Together".During 2009–12, new memberships, retention rates and time spent on the site decreased.In July 2012, the 78-year-old e Harmony founder came out of retirement to become chief executive.
In the late 1990s, Warren said he decided to test his theory that certain characteristics can predict compatibility and lead to more satisfying relationships.