How to figure out what is causing GRUB recordfail

Question

I had the problem of GRUB_TIMEOUT="1" having no effect. Just like in these questions 1 2 3. Setting GRUB_RECORDFAIL_TIMEOUT="1" accomplished what I needed. A related article. But I am not certain if this is the (GRUB-designer-)intended solution to my problem. Should I instead be fixing whatever is causing the recordfail to trigger in the first place?

How do I figure out what is causing recordfail to be triggered?

Observations/attempts:

• I tried running both grub-editenv create and sudo grub-editenv - unset recordfail. Followed by sudo update-grub. No visible results.

• In the file /etc/grub.d/00_header in the function make_timeout() there are the following lines:

if [ "\${recordfail}" = 1 ] ; then
  set timeout=${GRUB_RECORDFAIL_TIMEOUT:-30}

if [ "$recordfail_broken" = 1 ]; then
  cat << EOF
if [ \$grub_platform = efi ]; then
  set timeout=${GRUB_RECORDFAIL_TIMEOUT:-30}
  if [ x\$feature_timeout_style = xy ] ; then
    set timeout_style=menu
  fi
fi
EOF
fi

(I don't understand the syntax in the second excerpt and why there is an if-clause inside an if-clause.)

I changed the timeout in the second excerpt from 30 to 50 and, after sudo update-grub and a restart, observed that the GRUB timeout at boot was indeed 50 seconds.

• I also verified that in the grub console at boot echo $grub_platform yields efi.

Extra info:

Current /etc/default/grub (the colors at the end don't work):

# If you change this file, run 'update-grub' afterwards to update
# /boot/grub/grub.cfg.
# For full documentation of the options in this file, see:
#   info -f grub -n 'Simple configuration'

GRUB_DEFAULT="0"
#GRUB_TIMEOUT_STYLE="hidden"
GRUB_TIMEOUT=2
GRUB_DISTRIBUTOR="`lsb_release -i -s 2> /dev/null || echo Debian`"
GRUB_CMDLINE_LINUX_DEFAULT="quiet splash resume=/dev/mapper/ubuntu--vg-swap_1 sysrq_always_enabled=1"
GRUB_CMDLINE_LINUX=""

# Uncomment to enable BadRAM filtering, modify to suit your needs
# This works with Linux (no patch required) and with any kernel that obtains
# the memory map information from GRUB (GNU Mach, kernel of FreeBSD ...)
#GRUB_BADRAM="0x01234567,0xfefefefe,0x89abcdef,0xefefefef"

# Uncomment to disable graphical terminal (grub-pc only)
#GRUB_TERMINAL="console"

# The resolution used on graphical terminal
# note that you can use only modes which your graphic card supports via VBE
# you can see them in real GRUB with the command `vbeinfo'
#GRUB_GFXMODE="640x480"

# Uncomment if you don't want GRUB to pass "root=UUID=xxx" parameter to Linux
#GRUB_DISABLE_LINUX_UUID="true"

# Uncomment to disable generation of recovery mode menu entries
#GRUB_DISABLE_RECOVERY="true"

# Uncomment to get a beep at grub start
#GRUB_INIT_TUNE="480 440 1"

#GRUB_HIDDEN_TIMEOUT="2"
GRUB_DISABLE_OS_PROBER="true"
GRUB_RECORDFAIL_TIMEOUT="1"

export GRUB_COLOR_NORMAL="green/black"
export GRUB_COLOR_HIGHLIGHT="light-green/black"

I think my system uses UEFI (laptop from 2017 maybe), but I'm planning to switch my boot to legacy (BIOS?) mode soonish (due to a kernel parameter needed for an SSD to boot).

I'm using LVM, but not encryption. /boot is on ext4 under LVM.

Kubuntu 18.04