It's simple, it's because both parties(or everyone involved) have to actually be interested and both parties have to give each other some type of value for it to be sustainable.
Often you have people with a lot of capital and experience, just using the relationship to get some type of emotional value or a way to spend some of their down time, with no actual intention of building something. Than on the other hand you have people who are new and/or have no actual value to give to the more established people, they are just looking for some type of hand out or learn things for free.
A lot can be accomplished if both parties are serious, dedicated and form a plan. Most people make these groups and discuss things via text... that is not serious. Maybe for investing you can do that, for day trading futures text communication isn't taking things serious.