What is the common opinion about age and work?

There is a widespread assumption that work gets harder after 40. But in most organizations work gets dramatically easier after 40.
    The responsibilities may be heavier, but after 40 you should be valued for your experience, know-how and judgment, rather than for the ability to work 18 hours every day. Most of the major rewards of success tend to accumulate after the age of 40 — if you do the right things before that watershed birthday.
    What are the right things? First of all, do your homework; learn every thing you need to know about your business or profession before 40. Second, develop your own style. Before you’re 40, learn what you’re comfortable with, whether it’s in the way you dress or simply the small touches that set you apart. Third, put your emotional life in order, if possible. It’s a great help, when climbing toward the higher rungs of the career ladder, to be happy in life, rather than to find yourself mired in emotional crises. It’s hard enough to succeed without taking on personal problems that sap your energy and divert your attention. Besides, unhappiness is like a disease — it gradually eclipses interest in everything else.
    Fourth, know your weaknesses. Accept the things you don’t do well, can’t stand, won’t do.
    Fifth, know your strengths. You’d better decide what you’re good at, too, and recognize the things you enjoy doing and do better than anyone else. Whatever your role, knowing who you are and what you’re good at is critical for success.