Assuming you looking for partner in Business.
There are no successful partners and unsuccessful partners in business/startups.
Rightly said by one of the author 'When you choose your partner in business choose wisely'
According to me partner should be a better half version of yourself. He/she should find the idea of business as enthusiastic as you do , he/she should have the ability to understand the ongoing hurdles and resolve these , he/she cannot be just a helping tool but also should be visionary as you. If goals of partners are not aligned properly over the period of time partners are tend to be separated.