Has your dog ever got hold of something he shouldn't have? You've ended up chasing him round the house trying to snatch it back, you try your best to keep everything out of his way but uh-oh he's got hold of your favourite shoes or some dirty underwear in front of guests! He won't drop it, he thinks it is a great game with everyone chasing him! Well he doesn't get this kind of attention when he plays with his own toys! He'll do this again, look how fun it is!! haha
Well teaching a reliable leave it, take it and drop it, means you won't have to worry about him embarrassing you, the annoyance of having to chase him and your best shoes getting ruined.
Why not play games while he has his own toys, so he thinks this is fun instead? Why not get an item he is allowed to play with and then make it as exciting as possible, so when he drops the item he isn't allowed to have, he is rewarded with the a fun game with you instead (this isn't a permanent way of getting your dog to drop an item, it is just temporary until you have taught the drop it cue). This also means you don't compete with him for items and therefore avoid resource guarding in the future! If I had something and someone snatched it off me, I would probably guard it too!
Once your dog is reliably dropping on cue, he can be rewarded with the ball been thrown or a high value treat, such as the video shown.
Remember training should always be fun and rewarding.