One of ironies of mindfulness is that it's still possible to be forgetful, klutzy, or even distracted while doing our best to pay attention. Why? We are choosing where to focus and so there are, by necessity, bits of information that aren't getting full laser treatment. It's simply not possible to be mindful of everything all at once. That's beauty of it.
You can shine your mental high beams on, say, fully connecting with every person you talk to today. While being very aware of your interactions with others, you might trip on edge of carpet.
Clumsy and mindful may seem like strange bedfellows, but they are intimate nonetheless.
True story: I know a reference librarian who was in habit of reading while walking. One day, she was walking two blocks to her house during her lunch break while reading a new book. She was so completely focused on words she was reading that she tripped on sidewalk, landing in a heap right there on Ash Street.
Fortunately, this happened in front of fire station, and paramedics came to her aid immediately. Unfortunately, in addition to her badly-bruised ego, she broke not one but both arms.
The book she was reading? "Coping With Attention Deficit Disorder" You can't make up this stuff!
Mindfulness doesn't lend itself to multitasking-- especially when we need to watch where we're going. One-track mindfulness is ideal, but two tracks can work if one of them involves repetitive physical activity. Breathing, washing dishes, eating, walking, sweeping, swimming? Perfect. Tack on another--like reading--and you'll end up stumbling, too.