So social convention makes a person fearful? Isn't there something terribly sad about that?
It's more that social conditioning causes us to feel anxiety about many things. Is that sad? Not really, it keeps us civilized. Look at it this way, without it, we wouldn't even be toilet trained.
If I desire power, I may want the influence to get things done my own way, and when I want them done. Power would eliminate many sources of frustration in everyday life. That's not related to fear, it's the positive advantages of having control.
If I desire great wealth, it's because money helps to buy and obtain the things that can make life easier, more comfortable, more pleasurable, more interesting, etc. That's not related to fear, it's the positive advantage of having a great deal of money.
Not everyone is motivated by a fear of being a failure, although I'm sure that is true of some people. I honestly think I've been motivated by a need to succeed, to live up to my own standards for myself, and I don't think I ever worried about being a failure because I've never thought of myself as a person of no merit. Fears (particularly social anxieties) probably inhibit more people than they motivate. Fears are better at helping us to avoid things than they are at pushing us toward positive goals. A really profound fear of failure could keep one from doing anything, rather than trying something and failing at it.
These days, because of the economy, lots of people worry about losing their job, their house, their car. For some people these are real concerns, there is a danger they can lose their source of income, and with it, their home, their car, and everything else. Some have already lost their jobs and incomes and are faced with basic facts of survival--how to pay for having a roof over one's head, how to pay for food to feed oneself and one's children. If one has limited resources, it's difficult to reduce such anxieties because there is little control over the situation causing such stress. Some people can cope better than others by virtue of being more ingenious or creative about tackling the situation. Some people can simply cope better with feelings of anxiety (they may have religious faith, or self confidence, or more flexibility, etc.).
Real worries about having one's house foreclosed on, because one just lost a job, are different than worrying about what people will think of you if you live in a modest home rather than a high-end abode, or if you drive a cheap used car rather than a brand new, fully loaded Mercedes. People who need to have the symbols of status, just to impress others, or to make themselves feel worthwhile, are being driven by unhealthy anxieties and insecurities. Those people would be better off ridding themselves of such fears and developing a better, more positive sense of self. If you constantly worry about what others will think of you, in terms of social status, you are always at the mercy of others opinions and attitudes. You'd be creating a self-perpetuating situation of anxiety for yourself. That sort of emotional baggage really should be ditched. Some social anxieties are inevitable, and some are likely beneficial, but others can be destructive. It's the latter ones we have to try to modify. That would free our energies to be directed toward other (hopefully more positive) things.