Frequent, and Not Good
がち says something happens often — and almost always something you would rather avoid.
- 冬は風邪を引きがちです。(I tend to catch colds in winter.)
The negative slant is built in. ×成功しがち is odd, because success is not a problem.
Against っぽい
| Pattern | Sense |
|---|---|
| っぽい | an inherent trait — that's how they are |
| がち | a frequent occurrence — it happens a lot |
忘れっぽい人 is a forgetful person; 忘れがちな点 is a point that often gets forgotten.
Against ~やすい
Also close, and the difference is real:
| Pattern | Sense |
|---|---|
| やすい | easy to — a property of the thing |
| がち | happens often — an observed pattern |
壊れやすい means fragile by design. 壊れがち means it keeps breaking.
Form
It attaches to the ます stem, and behaves as a な-adjective: 遅れがちな電車.
With nouns it means "with a lot of": 曇りがち (often cloudy), 病気がち (sickly).