Be patient - lesson we learned from Caius swimming lessons

As the first time parents, we are not sure about when it is the best time to take our baby/toddler to swim. Also we are not sure when we should start those quite formal training to let them to learn swimming.

Here is our experience:

We took Caius to swim classes when he was like 7-8 months - there are those baby and parents' classes - one instructor and five parents/kids - and the instructor will teach some basic stuffs - more like how to let your kid face up and face down etc. It is more like playing with baby in the pool with proper techniques and get them to do some activities (like crawl/walk cross a floating board and jump). Caius didn't like it at all. He cried normally half of the lessons. My friend also took her son, who was 4-5 months to the same class and he loves it! He is so calm and zen in the water. We thought it is just Caius didn't get familiar with the instructor or the environment so we kept at going but it is pretty much the same. He would cry and didn't enjoy the class at all. Some of my friends said it is because he was a bit too old and can sense a lot of stuffs so he didn’t like it. If we took him 3-4 months, he would be fine. 

Then we took Caius to learn - like semi-class with another kid and one instructor to teach them when he is close to 3. It is a disaster. He now doesn’t want to go to swim at all. We have to convince him it is only he and daddy (no instructor) and it is only for play for 2 weeks, before he is willing to try again. 

So? This experience teaches me that it is no rush to sign the kids up to learn things. As parents, we are afraid that we might be too late to start them on something but the kids would naturally like it or dislike it. We should be a bit patient and just let them go at their comfortable speed. 
And I was wondering how come I didn’t learn from my other experience -when we took Caius to Gymboree classes before he was 1, he was so afraid of everything and didn’t like to be there. But after 1, he was ready for the social interactions and loved to be there. So we were telling our parents - don’t push him to socialize or learn, he wasn’t ready then and when he is ready, he catches up quickly.
This summer we would take him to play in the water and not really trying to force him to “learn”.