puny
Very small, weak, or not good enough.
Puny means weak, small, or unimpressive, especially in a disappointing way. When someone calls an effort puny, they mean it's pathetically small compared to what's needed. A puny pile of firewood won't keep anyone warm through the night. A puny serving of dessert leaves you wanting more.
The word often describes physical size or strength. A kitten's puny meow barely makes a sound. A bully might mock someone's puny muscles, though real strength has nothing to do with insults.
But puny works beyond the physical, too. A puny excuse for not doing homework won't convince your teacher. A puny apology that sounds halfhearted won't repair a damaged friendship. When a problem requires serious effort and someone offers only a puny attempt, the gap between what's needed and what's given becomes painfully obvious.
The word carries a note of contempt or disappointment. Calling something puny suggests it falls far short of expectations. Your first attempt at building a treehouse might look puny compared to your final design, but that's how learning works: you start small and build toward something better.