>>8691083They crack over time when they stay connected.
The reason is quite simple, absolutely fatal and also the reason why we get so many hairline cracks and discolored pieces these days: somewhere around a decade ago Lego changed their plastics to clear ABS that they add pigments to during moulding in order to cut costs and not having to rely on pre-colored plastic from other companies (same as with the baseplates).
That stuff gets used for nearly every standard brick including clips which before were made from a slightly softer plastic that was actually a bit elastic while the current one is rigid as fuck.
Seriously, if you have any old sets still built that were never combined with new ones then check out the clip pieces on them: they are less shiny, feel different and softer and also make a different, duller sound when you gently bang them against each other compared to new ones.
The softness/flexibility gets even more obvious with flag pieces due to their size.
