Pretty typical! The attention span at four is still pretty short, and kids are immediate in their experiences; whatever is in front of them this minute is what they are invested in.
You can use that to your advantage, actually. She's probably old enough to help with wiping the paints clean, or making the oatmeal, which may draw her further in enjoying the results of her efforts. I do this with my grandson, now going on five – and it enriches my own day to get into his experience from his point of view.
What I notice from a child's point of view is that life is bursting at the seams with newness and adventure, and the doing is so much more rewarding than the result. A clean paint tray is lovely from an adult perspective, but making the paint muddy is so much better (I'm an artist, and have muddied up a lot of paint in the process of making art), wiping out muddy trays is great, watching how water, brushes, or paper towels interact with paint and surfaces is quite a wonderful and scientific process in itself.
Or making oatmeal – how cool! See and feel the textures, sounds, movements, smells as a child does, and you've got something close to magic.
I just kept my grandson for the second 2-night sleepover in two weeks, and I knew that he'd be easily distracted by X while I was preparing Y for him. So I make it a "team" project, and he's right there and ready for Y as soon as it's ready to go. And I have a blast being on his team.