After visiting Phuket last year, I thought maybe I can try a different place this time. However not sure if Koh Samui is any better in terms of beach quality and environment including nightlife?

Advice would be greatly appreciated.

Do people still lay on the beach in Thailand etc?

Haven't been to Koh Samui but Phuket 16 years ago was a place we decided didn't warrant a return.
Have no idea what it's like now but if you went last year why on earth would you think of going this year.

I'll give both a miss.

Just found this and thought you might be lacking in constructive 'advice'.

We have been to both. There are pros and cons with both islands. I think it's well worth you trying Koh Samui out and judging for yourself.

It depends really on what you're looking for. For nightlife, we've found that Chaweng Beach area has deteriorated in recent years and is now a haven for bodybuilding swaggering 'blokes' who like a fight in Soi Green Mango late at night. The beach though is comparable to Patong, although unlike Patong, it has lots of hotels between the beach and main road. Lots of couples out and about in the evenings......And you can avoid Green Mango strip! Lamai has a wonderful beach, some chilled out bars and generally a younger vibe.
We preferred Samui over Phuket at the time, but it's about 5 years since we were at either so they may have changed again. I'd definitely give Samui a try. Get your seasons right though......as Samui is in the Gulf it has a different rainy season to Phuket.

I've been to both recently, and I'd say it really depends on what you are waiting for...

Phuket is all about nightlife, traffic, tons of expats, etc. But it's still a good place to enjoy your vacation.

Samui is different, more "chilled out", the weather can be different as mentioned before. Both are beautiful places, let's say that Samui is maybe less overcrowded, and I got the feeling it's not the same kind of tourism there too. Then obviously from Samui, you can take 2/3 days to visit other islands

Hello,
If you are looking for a city with more atmosphere, festive but also with beautiful beaches then I will choose phuket. Koh Samui unless this festive atmosphere, but there are paradisiacal beaches with few tourists