I dare to say it depends a bit on the rest of the chart as well. A Sag with Capricorn Mercury and/or Venus is likely to be slightly more dependable (unless other factors suggest differently.)

Also, personal choice is another key factor for Sags. There are Sags one CAN depend on! However, if we should ever come to feel that we are being "pushed" down a path we didn't necessarily chose for ourselves - say because of external responsibility, which robs us from our frantic need for personal independence - we get claustrophobic in every sense of the word. That's when the inconsistency, independency, selfishness and what-not kicks in. Freedom, in all of its forms, is of massive importance for us. But given the freedom; we just might *choose* to do the right thing afterall. So there you go: you CAN depend on us! (...for the time being, anyway...)

For me, I like to think that there's nothing I wouldn't do for the ones I love. But if they start placing heavy doses of obligations on my shoulders, they're just gonna have to expect me to fake an illness every now and again...NOT that it's a side of me I'm proud of - it's just that deep down, I'm a typical Sag afterall.