I can't remember the exact quote or its authoer, but it's like that: "The best for of government is a good dictatorship, then it's a good oligarchy, then it's a good democracy, then it's a bad democracy, then a bad oligarchy, and finally a bad dictatorship". And the problem with dictatorship is that a bad dictator can succeed to a good one. So while Singapore is currently a well managed country, we don't know who will success to Mr Lee Hsien Hong, and if that person does not turn out to be good, he will probably not encourage technological progress.
On the other hand, democracy is some kind of middle ground. Yes, it's a popularity contest what you say, politician can lie or be short sighted (we have examples of this with France suing Google over its ranking algorithm, or with the US policies in term of imprisonment, just to name a few), but on the overall democracy guarantees more stability than a dictatorship does.