Why won't he take it to the next level?

Me and this colleague have been flirting back and forth with each other for quite some months. I know I was the first to start this flirtation but he's been flirting back. I jokingly call him by his name for no reason, I touch him, I stare at him, iniate convo. He touches me, gives me compliments, smiles and winks at me, is protective of me. When I dressed nicely for a party he kept complimenting and staring at me. I thought he liked me somehow. But he's never made a move. I thought he'd ask me out. But nothing. He won't text me to say hello. Why though?
Why won't he take it to the next level?
Post Opinion