There is an even bigger reason to found as a pair or trio: a partner in the trenches with you!

Founders accept little money and work non-stop for YEARS. They are massively vested in their company succeeding. The difference between working with my co-founder and working with my employee could not be more stark.

Still if you don't plan to take money, and you plan to have a lifestyle business, then being a solo founder can make alot of sense. Smaller profits can float one founder more easily than two or three, and 8 years later it is hard to stay fully aligned. with a co-founder you are married forever to the partner.