Obviously mileage will vary based on the company, but try to generalize if possible.
Large companies some of the above can still remain true, you get job security through company stability, total comp packages can be much higher and more reliable. Company budgets are bigger so your products can sometimes have a much larger customer impact globally. More availability to move between teams and meet new coworkers or switch offices without much risk.
Medium sized companies are my favorite where the hair on fire foundation was already laid, product market fit is establish, but company is still private and growing quickly. Less risk here but still decent upside and less of the large company regulatory and compliance annoyances that impede velocity.
And in my experience sometimes the size of the company has less to do with quality of life than work culture.
The perhaps biggest downside of working in a big company is politics. You are no longer working to provide value to customers. Instead, you are playing a game of politics to get ahead of your peers. Sometimes these are correlated - you can get ahead by providing value to end-users, but often there is no correlation at all. After a while this really started to get to me to the point I could no longer stand it.
In terms of learning, I found both environments to be similar if you are motivated. It's true that in a startup you are forced to wear many hats and learn about things outside of your comfort zone. However, big companies will often give you these opportunities as well, they just won't force you take them. It's easy to become complacent. In a startup environment you can't do that.
In terms of risk-adjusted payoff, working for a big company is probably a much better choice than working for a startup.
Personally I prefer startups or small companies at this point, I don't think I could deal with the politics in large corporations again.
For example I was running a team of five devs a year after graduating - that would not have happened at a big company.
I also got the chance to architect complex systems within my first 2 years - again that would not have happened at a big company.
On the other hand by moving to a large tech company my pay quadrupled and I was able to focus on growing my pure coding ability.
I’ve also had the opportunity to solve complex dev problems that we would have just ignored/hacked around in a startup.
Probably my most frustrating experience is that big tech companies are biased towards big tech company experience. My extensive management experience was heavily discounted and I had to join as an IC. It took me almost 5 years to get to the same management level (director) at my current big tech (non-FAANG) company.
The only advantage to large companies is if there is a large presence in your area, moving internally between jobs is relatively easy if you want to change things up.
Advantages of small company:
- Privately owned so no stockholder BS or the constant downsizing/offshoring accounting games.
- Most time-wasting corporate stuff is very minimal at a small company. At large corp you could spend hours upon hours doing the mandatory annual security training which ironically required Flash installed to run the big brother tracking video course. Same for ethics, HR and other corporate-y trainings.
- No real politics. Large corp it was common to run into people that didn't contribute anything to the products/solutions. It appeared they existed to slow things down and act out Dilbert comic strips. This can really wear on you. Watch the movie Office Space.
- Want to try a new tech out? Talk with a couple people, give it a whirl - it has to have some purpose though. Large corp: "no, we use XYZ, we've always used XYZ"
I love small companies. Clearly, not any company will do - there are small companies that generate quite a bit of profit, so you don't need to worry about tomorrow as long as you're doing your job.
I'm not into startups - AT ALL - (at least, the US version of them), which basically pretty much promote "work your ass off - overtime, and the like -for pretty much low pay", with the possibility of making it big being insanely small.
(disclaimer: I do have a company, with a single employee - me, but I don't see myself as a startup; I do have collaborators; I don't ask for overtime, we always agree on "this is the task at hand, and this is what that will cost me")
In medium-sized org, you have more room to grow in terms of projects, responsibility and money. Usually, you have fewer limitations and your projects would have a higher impact. General engineering culture is still the most important factor following compensation. You want to find a place where you will get paid well and you will learn the best practices and tech.
With a small company, the software is not a "cost center".
Everyone has to pull an oar. You can tell pretty quick in say a 4 person company if someone isn't contributing.
No room for politics.