So, I see the great scorn for this unit and I have to say, most points I see are valid. Dreanoughts are overpriced, lack the firepower, movement, you can build War Suns instead, etc. Nevertheless, having played through the years, I regularly see people build them. And while I am sure this sin't the first place this is pointed out, it's my place to wonder about it and I bet there are several smart posters who could add to the discussion.
The question is why build them? Well, while I agree with the general negativity towards them, and agree they could have been designed better, I still see a role for them in the game. Sometimes, and in certain moments, there just isn't a better thing to build. Maybe you are producing a low number of units and yet have several resources to use. Maybe movement isn't as big a factor when you build them. Where else would you put an admiral? The problem I see is that their uselessness is generally pointed out in a vacuum. As in, "For the same tech to make them effective, you can build War Suns instead." Yes, and I build the War Suns. But there are inefficiencies in the game. Maybe you can't tech up something better because something another player did, and maybe you have a ton of red tech planets? Or "Why would I spend the resources on dreadnoughts when I can build War Suns? Because maybe your WarSuns are on the table, and you can't build infinate cruisers without busting your fleet size limit.
All I am saying is not everybody has the perfect situation in every game they have of Twilight Imperium. In fact, if your opponents are good, the sheer changes in each play of the game will lead to situations where you will need them. And red-headed stepchild though it may be, I don't see a justification to entirely abolish or ignore them. Am I alone?