[capableweb]

Give a read to "The Cathedral and the Bazaar" and subsequent essay "Homesteading the Noosphere". They'll give an overview of different software designs, including the management of building those designs, in a open source/free software context.

Both development models are OK, and plenty of people are comfortable with both. I'd actually argue that most early/not-"modern" FOSS software have had the model of "you're welcome to contribute, but we ultimately own the codebase and therefore decides what goes in. If you're unhappy, feel free to fork", and it's not until lately, that some projects have decided to merge almost whatever people contribute.

Some projects even go as far as giving people direct write-access as soon as someone has got a PR merged, but I don't think that's very common, neither is the "merge without strict review" model you seem to referring to.