the fact that something is not good enough or is too small in amount

Economic growth is hindered by the inadequacies of the public transport system. 经济发展受制于公共交通运输系统的不完善。

The inadequacy of the budget is likely to cause problems. 预算的不足有可能会导致问题。

a lack of confidence that makes you feel unable to deal with a situation

I always suffer from feelings of inadequacy when I'm with him. 和他在一起时总觉得自己不如他，这让我感到不舒服。