The most common excuse people give for pre-marital sex is "we should find out if we are sexually compatible." Two problems with this.
#1 It's widely accepted that the longer you are married, the better sex becomes. The first time you have sex with someone is usually not the best.
#2 If you don't have any experience, then you haven't developed any tastes.
If you both wait until you are married, you are both virgins when you are married. You have NO experience so you aren't likely to have developed certain tastes about sex. You might be intrigued with different positions, role-play, oral sex, anal sex, toys, handcuffs, candles, feathers, ice, bondage, and maybe even kinkier things. But you don't know what you like and don't like yet. You will discover your tastes TOGETHER. You aren't likely to love kink if you haven't ever experienced it. And if you try it with your spouse and he or she doesn't like it, then you aren't likely to get kinky enough for it to become important to you. You won't even know how important it could be to you.
The lovely thing about discovering sex together is it truly enhances the bond. The sexual bond isn't just about pleasure, hormones, and vulnerability. It's also about discovery. And I think the importance of this discovery is undervalued today.
The problem with incompatibility isn't that people have too little sexual experience before they marry. The problem is that they have too much. Each person who has experience with sex before marriage has become a specialist. Then the task of choosing a mate includes finding another specialist who fits you. But if you don't specialize before you marry, then you and your mate will specialize together, and you will have harmony in the bedroom.
Most of the people saying "you need to find out if you are compatible" are coming at the question with their own experience in mind. They are assuming that one of the individuals will have had experience. But that's not always the case. And if it is, then you should be open if the person you want to marry is a virgin and recognize that some of your specialization might have to change. But it doesn't have to be bad or even boring. Rediscover your love of sex with your new spouse, especially if they are a virgin. And if both of you have experience, then forget it. Try to find common ground. Marriage is all about compromise. If you can't compromise in bed, then it's probably going to manifest elsewhere first.
One final thought. If you are one of the people who says "you need to test drive the car before you buy it," fine. Are you willing to wait until you are ready to "buy" the car before you test drive it? Are you willing to wait to get engaged to this person before you have sex? No? Then this argument is nothing but a red herring. You are having pre-marital sex because you are immoral and can't control your urges. Stop trying to act responsible because you aren't.
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