Just some off the top of my head, from my own experiences when I was still naive and ignorant (and I still am), and from observing others.
4) You can also be removed from your role a lot faster and be forced down if the team (or worse, the investors) feel you're not ready and they feel the company requires adult management. For some people, it's true. But in some cases, you can get really buried because of petty issues, or in worst-scenario cases, forced out and left hanging to dry. You may come out of the experience having learned a lot, but you may also come out of the experience very bitter. See recently submitted article about Khalid Shaikh, regarding YouSendIt, Noah Glass of Twitter, Eduardo Saverin of Facebook, etc. Yeah, all of these guys probably made big mistakes and probably didn't deserve to be one of the senior guys. But the point is that they also didn't get a lot of help to develop themselves, whereas at a big company, the structure is in place to help develop people who need it (not always, but more often than in startups where everyone has to pull their own weight or die). Another recent alleged example is Naveen Selvadurai of Foursquare, though that guy has done a good job of taking the high road if it's true: http://www.businessinsider.com/naveen-selvadurai-tried-to-fi...
5) The level of transparency and all the good stuff that comes with it is all dependent on the level of integrity of the startup's leadership. There are lots of stories of founders who lie, mislead, and misuse the startup's money.
6) You can help shape environments, but it is also a natural psychological event that your environment shapes you. If your founders are domineering, arrogant, and generally assholes, it will be hard for you to influence the company, especially since most of the early hires will either be similar or easily cowed into groupthink. If you're not up to the task of standing up, you either become one of the cowed sheeple or get pushed out. It's sad if an startup's (or any organization's) culture is like high school, but it can happen.
7) I'd say it really depends on the leadership's philosophies. If it's a business type who's like "I'm the CEO, this is my leadership group, and you guys are just code monkeys", I'm betting you probably won't see this kind of culture where everyone can be involved in the hiring across the entire organization.
8) Already addressed somewhere in these comments.
9) Politics can exist in smaller companies too. And when the group is as small and tight-knit as startups are supposed to be, if the politics exist due to poor leadership and poor culture, it will be an even more painful experience than in a big company. After all, in startups, you can often spend all your time with the team when it's crunch time. In big companies, more often than not, you have the option to go home and leave work at work. It can become a lot more personal in a startup if the culture is bad.
4) You can also be removed from your role a lot faster and be forced down if the team (or worse, the investors) feel you're not ready and they feel the company requires adult management. For some people, it's true. But in some cases, you can get really buried because of petty issues, or in worst-scenario cases, forced out and left hanging to dry. You may come out of the experience having learned a lot, but you may also come out of the experience very bitter. See recently submitted article about Khalid Shaikh, regarding YouSendIt, Noah Glass of Twitter, Eduardo Saverin of Facebook, etc. Yeah, all of these guys probably made big mistakes and probably didn't deserve to be one of the senior guys. But the point is that they also didn't get a lot of help to develop themselves, whereas at a big company, the structure is in place to help develop people who need it (not always, but more often than in startups where everyone has to pull their own weight or die). Another recent alleged example is Naveen Selvadurai of Foursquare, though that guy has done a good job of taking the high road if it's true: http://www.businessinsider.com/naveen-selvadurai-tried-to-fi...
5) The level of transparency and all the good stuff that comes with it is all dependent on the level of integrity of the startup's leadership. There are lots of stories of founders who lie, mislead, and misuse the startup's money.
6) You can help shape environments, but it is also a natural psychological event that your environment shapes you. If your founders are domineering, arrogant, and generally assholes, it will be hard for you to influence the company, especially since most of the early hires will either be similar or easily cowed into groupthink. If you're not up to the task of standing up, you either become one of the cowed sheeple or get pushed out. It's sad if an startup's (or any organization's) culture is like high school, but it can happen.
7) I'd say it really depends on the leadership's philosophies. If it's a business type who's like "I'm the CEO, this is my leadership group, and you guys are just code monkeys", I'm betting you probably won't see this kind of culture where everyone can be involved in the hiring across the entire organization.
8) Already addressed somewhere in these comments.
9) Politics can exist in smaller companies too. And when the group is as small and tight-knit as startups are supposed to be, if the politics exist due to poor leadership and poor culture, it will be an even more painful experience than in a big company. After all, in startups, you can often spend all your time with the team when it's crunch time. In big companies, more often than not, you have the option to go home and leave work at work. It can become a lot more personal in a startup if the culture is bad.