You have two problems: an agency problem and a knowledge problem.
The likely reason why your players weren't all happy with the outcome of the situation you describe is because you took away their agency. Generally speaking in D&D, the players' expectations is that they control their characters, not the DM. By taking a suggestion from one player and forcibly turning it into an action, you a) took away that player's control and agency; and b) denied the other players input into the decision.
A similar way to handle future indecision without taking away players' agency is to ask leading questions, rather than making declarative statements. For example: "So the paladin wants to charge in. Who wants to go with him?" This is extremely similar to how you phrased it, but by using a "soft" phrase like "the paladin wants", combined with the leading question "who's going with", you still give the players a chance to make choices.
The reason this type of phrasing works better is because of a neat little trick of human psychology. Humans, on average, tend to go with the default option, whatever that is. When players are arguing like that, it means they don't have a default, and get stuck with decision paralysis. By using leading questions, you're giving them a default (charge in with the paladin), while also leaving room for someone who really does want to do something else, to do so ("I stay behind and watch for an ambush").
However, the fact that your players don't have a default likely means that they don't have enough knowledge, either about your world, the situation in general, themselves, or each other. They're afraid to make a decision because they don't understand the consequences.
Fortunately, it's fairly easy to provide more information about your world (is it a place where mercenaries run free and ambushes are common? Is it reasonable for the players to be paranoid about entering dungeons because adventurers are known to die frequently? And so on). Providing information about a specific situation can be trickier, especially if the situation relies on them not knowing what to do (such as in puzzle rooms, in social situations, or in well-fortified dungeons). However, this is where you can encourage knowledge checks to help the players get more information. For example, take the paladin's passive perception and say, "The paladin notices a holy symbol carved above the door. You can make a Knowledge(Religion) check to know more."
Getting the players to understand their own characters and each other's is much harder. However, it's a fantastic way to reduce decision paralysis without needing to tip your hand with free information. For example, in a game I currently play, my character is a monk with a reputation for charging straight into a fight. Both I as a player and she as a character know she can do that because she knows at least two of the other characters will almost certainly back her up. She doesn't have to sit there and worry about what will happen if she charges in, because she knows: she'll punch the monster in the face, then the fighter and the rogue will follow and keep the monster from killing her in return. This in turn means that I don't sit there arguing with the other players about what to do - I just do it.
TL;DR: Make sure your players have enough information to handle any given situation without getting decision paralysis. When they do get stuck, provide default options to get them moving again without undermining their agency.