When I was a teen, I would never have considered a ceramic capacitor when I needed, say, 5 μF or more.  That automatically meant using an electrolytic capacitor, or in some cases, solid Tantalum.  But today, I can buy surface mount capacitors in 4.7 μF, 10 μF, even 100μF.

But wait.  When I actually got those capacitors in hand and measured them, they seemed to be lower in value than marked.  A capacitor has tolerance; I get that.  But if it has a -20% tolerance specified, I expect it to be at least 80% of the marked value.  The ones I got were way off.

I’m wondering if there is some kind of scandal about to break here, as the actual capacitances are so low in some cases. It’s like buying a dozen eggs in the market, and finding out that there are only 7 in the box. Perhaps the capacitors are marked in terms of “equivalent filtering capacity” compared to aluminum electrolytics? It is somewhat true that a lower value ceramic can often be used, due to lower equivalent series resistance (ESR). But like audio amplifier power ratings or battery mAH ratings, I still see it as basically lying. Heaven forbid someone needs to use one of these as a timing element.