Why is EXT4 filesystem mounted with both relatime and lazytime

I'm running Debian/Testing, with kernel 4.4: # uname -a Linux shaula 4.4.0-1-amd64 #1 SMP Debian 4.4.6-1 (2016-03-17) x86_64 GNU/Linux So I want to use the lazytime mount option, which is why I put the following in my /etc/fstab: # grep vg_crypt-root /etc/fstab /dev/mapper/vg_crypt-root / ext4 lazytime,errors=remount-ro 0 1 However, now the filesystem seems to be mounted with *both* relatime and lazytime: # grep vg_crypt-root /etc/mtab /dev/mapper/vg_crypt-root / ext4 rw,lazytime,relatime,errors=remount-ro,data=ordered 0 0 How can this be?