If it is a picture, I will post a comment no matter how many pages of comments there are :D:D:D
Other topics? It all depends on the topic LOL
Some authors are looking for many different ideas, some for help. Keep in mind, the way each of the replies are worded vary, mine may not be very helpful/easily understood but yours may be :D
Some topics the author may be wanting many opinions and will go with the most popular one. Kind of like taking a poll :D:D:D