The Metronome.
My dreaded enemy, the executor of truth and justice. All through out my early music life I despised the little machine that sat atop the piano in our living room. I would almost never use it, until my parents were tired of hearing me play piano scales completely wrong, and insist upon me using the white knight of meter that confirms my inability to play music. The metronome didn't take in my early trombone playing either. I thought I knew everything about the trombone (no really, you can ask my music teachers, I was a pain in the ass.) I really wouldn't take to the unbiased instantaneous humbling solutions until I reached college. Even then I waged war in my psyche on how much to use the instrument. At some point I must have given up because the likes of William Tell and Till Eulenspiegel were looming over me, and those cannot be learned properly without meticulous oversight of the humble metronome. Beaten into submission I gave in completely and began my life long study of unwavering time.
Look, the metronome is a wonderful tool that will expedite solutions to many problems in your playing. You should be using a metronome every day in your practicing. Use it in your warm up routine, use it with etudes, use it with sight reading, etc.
Want to know how to get ahead of the players around you and get the gigs or 1st chair on a gig? A metronome sure won't ruin your chances.
So go out there and admit you don't have perfect time, and sit down with your local metronome dealer so you can pick the best metronome for you!