You got it. Just like any negotiating deal the person with the most leverage wins. A HS senior with a good offer has leverage. A juco freshman has a little less, then juco sophomore, then junior, and a senior is in trouble unless they have a lot to offer. It still depends on talent and projectibility. The change in leverage is when someone makes a growth spurt or adds speed/power either as a pitcher or hitter. But all things equal and progressing as normal your best leverage is as a HS senior. Again, that does not completely playout in the draft if you look at history because a lot of guys (I don't know % because I don't study that stuff but I'm sure some here do or could find it) increase their slot by going to college or playing an extra year or two.