I disagree, if said player has a high ceiling and the amount you sign them for is low, that's low risk high reward. Garcia and Colon were, as much as I hate to say it, two guys who had past success, high ceiling, and didn't ask for very much money because of that.
Same with Beltre when they got him, that was actually just a steal of a deal, because for some reason everyone forgot he was playing in Seattle and still put up pretty good power numbers, plus his naturally excellent fielding skills, that was a low risk, very obviously barred injury was going to produce on the high reward too.
Same goes for Abreu when they got him on the cheap. I think any contract that's 10 years or over 20M per year is a high risk regardless of who it is, or how good they are.