Money
Money was never my reason for switching jobs, I know this is highly personal but the differences in pay between the 2 companies were all but negligible (<10%).
Nonetheless I’ll address some of the more minute differences in pay between the two.
Startup companies are small and as such usually allow their employees greater expenses, you can buy your choice of laptop or computer, lunch and coffee are usually paid by the company in full and generally speaking almost all work related expenses are paid in full.
Another thing is that small companies don’t need to try and cut down on employee salaries using some sort of trickery like big companies do, like giving a small base salary and counting the rest as “bonuses” or “expenditure”. This means you won’t get a de-facto pay cut when missing work or going on vacation. In countries where the employer pays social benefits according to your pay it also means that you get benefits according to your actual salary and not some low “base” salary, for instance in my previous job only 80% of my salary was considered for pension.
The other and to some the biggest allure of startup companies are the options you receive from the company, what it basically means is that if someone buys the company you can receive a relative part of the money. I think that if you choose a startup because of the possibility of striking it rich it is a mistake.
Most startups never reach the point of being sold, and even those that do usually take years to get there, and even on those occasions most times you will not have enough options and the sale price will not be that high so as to give you a huge amount of money.
If you are looking to join a startup in order to strike it rich you might be better off keeping your job and buying a lottery ticket every week.
On the other hand big companies have power in numbers such that small startups can never compete with, large companies might have a gym or some other facilities. Also large companies generally tend to have better offers on cars (lease), health care and other services.
Bottom line is that from my own personal experience if you count the added cost for health care, car ownership and various discounts it is very difficult to say which options pays off better at the end of the month. Maybe I’ll have a definitive answer several years from now :)