What does it mean?
Off The Bricks is best defined by its inverse, On The Bricks. To be On The Bricks is to be making little to no progress at something you hope to achieve while being in denial with others (and usually yourself) about how much effort (or how effective the effort) you're putting in.
Off The Bricks is to be motivated and to not let anything hold you back. Think of it like how you'd feel if you were carrying a load of bricks (on the bricks), vs if you weren't (off the bricks).
Where'd it come from?
I live in a house with a big bold brick fireplace taking up one wall of my living room. If I wanted to download or stream any content to my TV, the best place to put my laptop was on the hearth in front of that fireplace. Unfortunately the bricks and that laptop did not get along, and my WiFi bandwidth plummeted as soon as I put it 'on the bricks'.
My wife was pregnant with our first child at the time, and when she felt like it was too much effort to get up and move around, I used to joke with her that she was 'on the bricks' too. The only way to feel better, or for the laptop to stream better, was to get 'off the bricks'.