Capricorns are known for their practical approach to any issue, and compliments are not an exception. They want to hear useful and constructive praise only and are tired of abstract phrases that have in fact nothing to do with them. They will surely use positive words you tell them to become better and achieve more.
They love to connect the dots and would hardly appreciate empty phrases. It’s even possible that they will ask you to work on your words more to make them truly meaningful. However, if you get a compliment from your Capricorn acquaintance you can be absolutely sure that he or she is serious and you’ve done really great.