Could it be that Germany's vaunted Leopard tank actually sucks?

Apparently, the answer is maybe. It might not suck at the purpose for which it was originally designed -- stopping vast numbers of Soviet tanks pouring through the Fulda Gap and across the coastal plains of northern Germany (the U.S. was mainly responsible for the Fulda Gap back then) -- but it apparently has problems dealing with the realities of warfare in a less conventional battlefield:

Germany’s Leopard 2 main battle tank has a reputation as one of the finest in the world, competing for that distinction with proven designs such as the American M1 Abrams and the British Challenger 2. However, that reputation for nigh-invincibility has faced setbacks on Syrian battlefields, and placed Berlin in a uniquely awkward national-level dispute with Turkey, its fellow NATO member.

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The Leopard 2 is often compared to its near contemporary, the M1 Abrams: in truth the two designs share broadly similar characteristics, including a scale-tipping weight of well over sixty tons of advanced composite armor, 1,500 horsepower engines allowing speeds over forty miles per hour and, for certain models, the same forty-four-caliber 120-millimeter main gun produced by Rheinmetall.

Turkey, a NATO member that is maybe less than dedicated to the same human-rights principals that Germany applies in restricting its arms exports, is a Leopard 2 customer. Turkey used to employ the M60 Patton tank, a U.S. tank first employed in 1960. The Patton was woefully obsolete, and in the early 2000s Turkey bought a bunch of  Leopard 2A4 tanks. Despite being obsolete themselves, they were a big upgrade from the M60. Those tanks still make up the bulk of Turkey's armored forces.

It is rumored that the sale of 2A4s was conditioned on not using them against the Kurds. Nobody has ever confirmed that, but the Leopards were kept out of action against the Kurds for many years. In 2016, though, about a dozen of Turkey's M60 tanks were destroyed in action against the Kurds and ISIS, and Turkey sent in Leopards. That didn't go well.

In December 2016, it became clear that ISIS managed to take out about 10 Leopard 2s with relatively low-tech weapons. Since then, Turkey has asked for upgrades to the Leopard 2s it has. Germany, while upgrading its own fleet of tanks, has declined to sell upgrades to Turkey. That may be because Turkey is not the kind of customer Germany wants in terms of human rights. It also could be because Germany doesn't want the Leopard 2 to suffer further embarrassments. Having fought in a similar non-conventional battlefield in Iraq, the Abrams did not suffer the same kind of defeats the Leopard 2 apparently has. Germany might be seeking to avoid damage to the export market for the Leopard 2.