I do not think that economic changes always have a positive effect on society, but rather can have a fairly negative effect. If the economy in a certain society changes, people are going to have a hard time adapting to the changes, which is definitely a potential disaster. Changes in the economy effect pretty much everyone involved, and if people are having a hard time adapting to it, then it's obviously going to have a negative effect on their society. With people not catching on to the changes overly fast, the economy could slide drastically, which most definitely would be a bad thing.
Now I'm not saying that the effect is always negative, but it's not always positive. Changes could also be for the better, with the economy growing stronger with certain changes like improvement of transportation, growing industrials, and better manufacturing machines. These changes would almost definitely boost the economy in any given society because of the positive effects they would have. With these kind of improvements not only would things get done a lot faster, but they would also be done with better quality more consistently, which would make things sell more, which would up the economy a notch.