Grub's default kernel priority

I recently installed Arch on one of my machines. I installed grub in UEFI mode. While setting up Arch, I had installed linux-lts. I used it for some days, and later decided to use both LTS and regular kernel. So, I installed linux (regular) package. After its installation, I assumed grub to boot into the latest linux. But, it continued to boot into older linux-lts. I tried to regenerate initramfs and updated grub a few times but didn’t succeed. To get grub to boot in latest linux, I had to edit grub menu entries using grub-customizer.

Is this normal behavior of grub ? I had read somewhere that grub actually prioritize latest kernel if found and boots in it directly. Then, in my case why is this different ? Have I misconfigured something ?