How does collapsing comments by default help with readability?

Reddit's comment threads can grow extremely deep, with reply chains nested many levels below top-level comments. This structure is valuable for tracking individual conversational threads but can make a thread with hundreds of comments extremely difficult to navigate when trying to get a broad sense of the discussion. The comment collapsing feature addresses this by allowing users to minimize entire branches of a conversation with a single click. On desktop, clicking the small minus sign or bracket that appears at the left edge of a comment collapses that comment and all its replies into a single line. Clicking again expands the thread. This allows a reader to review top-level comments quickly, identify which threads look interesting, and expand only those while keeping the rest folded away. The visual result is a much more manageable view of a long thread. Reddit also collapses certain types of comments automatically by default. Comments that have fallen below a certain score threshold — too many downvotes — are collapsed by default and require a click to expand. This is a soft quality filter: heavily downvoted content is not hidden entirely, preserving transparency, but it is de-emphasized by requiring active effort to read. Some communities configure stricter collapse thresholds to more aggressively suppress low-quality contributions. For threads that have been active for many hours and accumulated deep reply chains, collapsing comments by default helps you find the most recent activity more quickly by allowing you to collapse the fully-developed older conversations and scan for newly posted replies. In practice, developing the habit of using comment collapsing — rather than scrolling through every nested reply — significantly reduces the time needed to survey a busy thread and helps you identify the most substantive conversations within it. For moderators reviewing a thread, comment collapsing also makes it easier to assess the overall structure of a discussion without reading every nested reply. Being able to collapse fully developed tangential branches and focus on the main threads of conversation is a time-saving tool during active moderation. For regular readers, developing the collapsing habit as a default approach to long threads is one of the more effective ways to extract maximum value from busy discussions without becoming overwhelmed.