Seriously, how do you think you'll do a good job if you don't like it? If you only work for the income, the best you can achieve is an average product. The difference between successful products and the others is the passionate work.
On the other hand, people that don't like their job can ruin the work of others and the smaller is the company, the bigger is the impact of only-for-the-money people.
Companies have a great responsibility in making sure their employees are happy, motivated and inspired. They should also limit the impact of bad apples. But, in the end, everything it's up to us, because...
Your work is going to fill a large part of your life, and the only way to be truly satisfied is to do what you believe is great work. And the only way to do great work is to love what you do.
- Steve Jobs
Image by Matthew Yohe taken from Wikimedia Commons licensed under the Creative Commons Attribution-Share Alike 3.0 Unported license.