Mark first wrote a post about the Co-Founder Mythology and Fred responded with a counterargument. Both of them focused on why a partnership makes sense or doesn't. One of the things I found missing in both posts is what exactly works or goes wrong. Here's my take after observing partnerships/co-founders/solo entrepreneurs for years. Equal partnerships or 50/50 splits usually fail! Trying to always be equal usually fails. After time, things go out of whack and it's irrelevant whether it's a start-up, a venture fund or whatever.
More important than arguing whether it's good or bad to co-found or go it alone, I find it much more interesting to think about why partnerships fail. I'm going out on a limb with this one but I am sure people will be happier than ever to argue with me about this point. Here's my take: if you start a business with someone in an equal partnership, either money or love will eventually kill the effort.
Let's start with money. No matter how equal you keep things, eventually one or the other person will feel that they earn too little or that the other earns too much. Don't take this to mean that both parties necessarily have different salaries. It's simple enough that one partner be married and have kids and the other be single. Obviously one party will have far greater financial burdens than the other. Because he or she have less cash to spend on themselves, they quickly can start to think that the other party has "too much". Then they start thinking about who "works" more since they both should technically be working the same amount for the same pay. Again, if one has family, there is less time in the day for work. Hence, the thought again arises that one is working more than the other, although both may actually be working just as much as the other. It's human nature to think like this. Some partnerships avoid this but most don't. No matter how hard you try to balance this out, it creeps in after time. There are multiple variations on this but the psychology of "money" usually will creep in and at the end of the day, money is just that: money (and each and every one of us has an individual take on it). It's the psychology behind money that causes us as individuals to do stupid shit!
Now on to love. Be it a male (typical) or female (still atypical) partner in a business. People either meet other people and start relationships or they don't. Those who do have one other partner involved in their "partnership". Say what you will but our significant others extensively effect how we view things in our business lives. Argue until you're blue with me but I guarantee you that your husband/wife can make your life a personal hell if they believe something to be out of whack with your business partnership. On the other hand, a partner in a business may decide to stay alone. Some people are able to be alone and focus all their energy on work (or whatever else). Yet many eventually become very unhappy with the solo lifestyle and start focusing their energy elsewhere....usually desperately trying to find love or at least "belonging" to something. This can totally distract from the needs of the business. Regardless of whether one is in a relationship or not, it has such a strong influence on a business partnership that chances are good it will kick the partnership in the ass.
I could go on for pages about how either money or love will eventually destroy an equal, functional partnership but my generalization above surely gives you my drift. Hence, I am on Mark's side about the co-founder myth. My opinion is that in the long term, you are better off going it alone. By "alone" I mean one founder clearly being in the lead and having 50.1% or greater equity in a business to make decisions (for details on this, go read Mark's post....no need to repeat here). There are a ton of examples where 50/50 partnerships work but I'd bet there are far more failed partnerships which were equal splits. If there were a way to research each and every one of those failures, I am quite positive that either money or love as I defined them above were the root of that implosion!