ouch
The technology does have some basic flaws.
As stated the charge is detonated by a proximity switch of some kind. The weapon effectiveness depends on the charge going off at an optimal distance from the target. If the charge detonates too far from the target the jet of molten metal will impact on the surface and have minimal penetration.
A screen of chicken wire set off the surface of the target a foot or so will cause some of these weapons to detonate too early. Many tanks have been modified with stand off screens to protect against these weapons. This is why the TOW is designed to attack from the top of the target.