Yes, anyone who has ever lifted seriously has experienced this. The back is behind you and by design is hard to hit with intention. That is until youve mastered the skill of that particular lift your executing. The primary role of the lats is adduction of the arm at the shoulder. Whats this mean in straight terms? Extend your arm in front of you, supinate your wrists and rotate your extended arm in a semi circular motion straight back behind your waist line. So the contracted short position is where your arm passes your waist and then a lil inward toward your rib cage. Its not a straight line so exercise execution should reflect this. Its no matter many cant effectively hit the lats properly as most fixed machines are a 1 size fits all application. Longer levers in the variation of the human anatomy of person to person and the origin and insertion points of an individuals lats all play a huge role in execution as well.
If your having a really hard time getting in the mood to do it for the day try straight arm cable pulldowns. Thats closest to the natural movement of a flexed lat. And superset directly with a compound back movement of your choice. Always engage the lat first cuz its almost impossible for it to catch up once the bicep gets the weight in motion. It should be a painful and piercing contraction in the lats