In Ubuntu 16.04, there is a bug in plymouth that it doesn’t automatically switch back when the boot process is finished. In fact, the splash screen is terminated and stayed in graphical terminal (VT7). Hence the user is stuck with a fsck screen output without login prompt that the user has to manually enter CTRL + ALT + Fn keys to login.
See this bug entry.
It takes me a while to come up with a workaround solution. Simply add the following line at the end of /etc/rc.local.
(sleep 1; chvt 1) &
However, I have no idea why simple ‘chvt 1’ won’t do the job but it works.