Question about Plymouth - logo on boot screen

Dear Community,

I have question to Plymouth. Like we know this is the application which provides the graphical "logo" screen when booting and shutting down my system.

I noticed I think issue but maybe this is not issue and this can be normal but I don't know why this is happen? Can you explain me? Of course now you thinking that I didn't say what is the problem so I will do this now. When booting my system I can see "ubuntu" logo screen with animation and is it normal but sometimes I can't see the logo and I can see animation but only with "ubuntu" text but like I said without ubuntu log. What is the cause of this situation? I can see that we have two packages. For example in my lubuntu system:

- plymouth-theme-lubuntu-logo,
- plymouth-theme-lubuntu-text

I think that now you will write that this I must write about this issue to Lubuntu Developers but like I said I have more then one computer and one of them have installed Ubuntu 20.04 and I have exactly this same issue. On another machine I have installed also Ubuntu 18.04.5 and I also have this same issue. Of course if it is issue because like I said maybe is it normal but is it very interesting for me why sometimes I can see when I booting my system text mode plymouth. When I shutdown my machine I see that I always have plymouth in ubuntu logo mode. Can you explain me how it is work? What program decide which package is working?