It's a process if you don't start "hand holding" from day one. The very first time I ever raised ducks, I toted them around in the front of my Tshirt to take them outside and would sit by them with a book while they ran around, talking intermittently to them. For hours. They were obnoxiously tame.
This last batch, 10 years later or so, I didn't do that with. And they hate me. By the time I realized they hated me, I had my work cut out for me.
For treats, I'd mash up peas, or even just wet their starter. I'd toss some, and eventually one of them would realize it was food and that it was good stuff. From there, I would start tossing it closer and closer to me or my hand. After a week or two, a couple would be brave enough to take it from my hand. The rest didn't get any but a little bit, to help entice them.
My big ducks, they think now that I'm the almighty food giver, door opener, and water cleaner. They listen for me and quack responses to me. My two baby call ducks I've been spending a lot of time with. They're not outright afraid of me, but nervous about being picked up. They're coming along nicely since they're only about 2-3 weeks old.
Next batch is coming (I hope!) next week from Holderreads. I'm going to play with them a lot and baby them to avoid this whole afraid, judgmental, standoffish thing I fought through with the older ones.
Just changing out food and water and saying a couple words to them is not enough. It's a time commitment to get them tame. I start talking to them before they see me, so they know I'm coming. Avoiding the mad dash to the corner. Then I go about cleaning/refilling. Then I'm really mean and keep my hand by the water. If they want some, they have to brave the hand! Battle of wills, it feels like.
Those ducks don't know how stubborn I am!
But there I am, a supposed grown up, talking baby talk and splashing my hand in the water trying to look harmless and make friends with ducks that hate me. My older ducks will hop in the baby pool while I'm splashing in it. Only had to sit there for 40 minutes until it happened and they couldn't stand it anymore. Progress!
One will make a mad dash at me if I have a worm in my hand. Luckily her greed overrides her fear. I'm not worried about using their faults against them. I also started holding them one by one in the evening when I get them in their building for the night. It used to be a fight. Now, they protest a little but settle down fast. I just held on until they quit, made nice with them, then released them free to leave from my lap. I never picked them back up to set them back down, I wait for the struggle to end, wait for them to calm down, then just pull my hands away. Two of them will remain sitting and act all cute. The Saxony one pauses for a moment and then leaves. But leaves calmly, so that's progress.