why does bootloader always get messed up when dual boot installing on another drive?

i have windows 11 installed on nvme1, including the efi partition.

the other drives don't have an efi partition.

after removing nvme1, i go and install another version of windows for testing purposes on ssd2 with 90gb unallocated space.
Installation creates the new efi partition, etc on ssd2.

With ssd2 still in the pc, when i put nvme1 back into the pc, it's own efi partition and all, and go to the bios to boot from nvme1, Windows boots into the repair screen.
It fails to boot into windows.

NVME1 and SSD2 each have their own efi partition. So why wasn't windows able to boot into NVME1 ?

NVME1 was removed and untouched during the installation of windows on SSD2.

I had to run the bcdboot command to fix nvme1.

because each time you install Windows that version of Windows tries to take over the boot sequence
the Windows boot-loader doesn't like living with anything else other then the last boot-loader version you installed.

this maybe of interest if you are dual booting with different versions of Windows
Grub2Win

its the Linux GRUB boot-loader for Windows.
best of luck Steve ..