I could never hold a beat. As a teenager trying to dance, I had two left feet. My sisters would try to coach me in dancing to 60's pop, saying "listen for the heavy beat, move to that beat". No good. Things would drift, I would get lost and nearly trip over my toes. I loved the music, I sang it in my head, I knew the tunes and lyrics, but dance ... no hope.
When I was forced to join in marching at school and in doing national service, if I could find the pace at all, I would find it slowly drifting away. Luckily I learned the trick of changing one's step by using one foot to kick the heel of the other. Bafflingly, sometimes I found I was still out of step.
When I started learning to play my sax, my teacher would say, "feel the pulse, tap your foot". Guess what, I found I couldn't even tap my foot. He said "play with a metronome". Nothing did more to put my time out, and I froze, terrified of coming in at the wrong time, so even playing the first note was a challenge. Left to my own devices, I could pick out the notes ... in my own time ... which was the wrong time.
Then things slowly started to change; things seems to be coming together now. When I played at the jazz camp in San Diego this year I was complimented for my sense of timing. What changed things? I reckon two things: firstly, I started making and playing to backing tracks. Unlike the harsh, insistent metronome, Band-In-A-Box gave me a warm, swinging, organic sound to play against. It was actually good to listen to, even without playing a note, and when I did attempt a few tentative notes, they sounded gooood against the pulse of the bass. And the second thing that changed flowed directly from that. I started to move. Not just tapping my toes, but starting to dance, to let the music flow through my body. These days the toes tap at the slightest hint of swing.
Now I have a long long way to go: I make mistakes aplenty, both in reading the music and in placing the notes. I struggle with phrasing, some passages are just too swift for me. But, hey, on a good day, I Got Rhythm.