The broad German coalition government of Olaf Scholz has many competing internal interests, and many are not keen to be involved in foreign wars.
Poland for one is keen to help Ukraine with the German made Leopard tanks it has, but the contract of sale only allows export of the tanks with the agreement of Germany.
So it was a pivotal breakthrough when the Chancellor agreed to allow supply of tanks to Ukraine, as well as supplying 14 from the German fleet. The Americans now have agreed to supply Abrams tanks as well. Free of EU shackles, the British had already gone ahead with support with tanks for Ukraine.
With Spring Offensives around the corner, Volodymyr Zelensky will need as many tanks as he can get.