How did the Weygand Line collapse so quickly?

Question

The Weygand Line I am referring to is the line established by Maxime Weygand in the aftermath of the hugely successful Fall Gelb. Immediately after the evacuation of Dunkirk, French soldiers were being repatriated back to France and presumably bringing back with them knowledge and expertise on the German's tactics. French military technology was also on a parity with the Germans, with better tanks (such as the Somua S.35) and artillery. Their lines were also anchored on the rivers Somme and Aisne. The advantages the Germans had was the number of divisions (142 vs Weygand's ~60) and the qualitative superiority of the Luftwaffe. Significant advantages, yet, it only took 3 weeks for the French army to utterly collapse.

How did the French army collapse so quickly? Were the German advantages in numbers and air superiority that decisive?

Answer 1

By June, 1940, the French army had been divided into three roughly equal parts. 1) One third was lost (captured) in the north when the Germans reached the English Channel south of Dunkirk (nearly all the British and Belgians but only a few French were evacuated), one third on the Maginot Line, and only a bit more than one third on the Weygand Line.

After winning in the north, the Germans concentrated most of their army, (including some opposite the Maginot Line), against the Weygand Line, giving them a nearly two to one superiority in numbers and weapons.

It's true that the outnumbered, outgunned French fought bravely and initially held back the Germans in "most" places. The problem was while they were "seldom" defeated on the Weygand Line, they "never" won. For instance, they could not quash any of the three bridgeheads the Germans had pushed across the Somme. Finally Rommel found an opening, pushed through, and won. Given the German superiority of numbers, one or two breakthroughs was sufficient to collapse the whole line.

I remember a ping-pong game I played as a child. Each point lasted 15-20 rounds. Overmatched by an older player, I seldom lost a point but never won. The final score was 21-0, after nearly 400 rounds. That's what happened to the Weygand Line.