The Goldilocks Zone: Campaign Length
The long and short of things: The shorter your campaign, the less investment your players will have in the story, but the more focused and experimental you can be.
I've run many games (though never as many as I'd like). The length of the campaigns has run the gamut from very short one shots (3 hours being my shortest), to an ongoing 5e campaign that will hopefully culminate at level 20. I've run games of all lengths between these extremes, and have had similar variety in the measure of their success. I'll tell you about two noteworthy ones:
After playing the excellent Lasers & Feelings by John Harper I became enamoured by the featherweight nature of its rules and decided to experiment with the format. I "designed" Maths & Mythos and brought it to some gaming friends to run an occult mystery set aboard the Titanic. Due to skill issues on both sides of the table the game ran on for like... five sessions? Perhaps even six? More than the story called for, and far more than the mechanics could support. The total lack of mechanical complexity resulted in tedious game play.
Another time I tried to run a one-shot of a wonderful game called Warbirds. It's a charming game of pulpy aircraft dogfighting and barfights. If you're interested in such things I suggest checking it out. However, it's a fairly crunchy combat system, and the three hour block I had set aside for it was simply too short to do it justice. I tried to cram in too many character dynamics, schmoozing and backstabbing at the pilot's clubhouse, and a complicated moving train combat using rules I'd never tried out properly. It was a fun time, but the format really throttled what could have been a very fun adventure if given the breathing room.
When planning a new campaign, it's worth considering the target length. Longform campaigns often seem to be the default assumption, but shorter campaigns offer their own pros and cons that could make them a suitable choice. In this article I'll be comparing the two extreme ends of the spectrum: one shots and traditional campaigns.
Story Depth and Exploration
The narrative is condensed in a one shot, focusing on a specific theme or event. It's ideal for trying out creative or unconventional storylines. They encourage experimental and off-the-wall scenarios, as there's no need to worry about long-term implications. Full campaigns allow for a more layered and evolving story, giving room for subplots and complex narratives. However, it requires careful planning to avoid narrative stagnation or constraints. They also demand consistent creativity to maintain engagement over a longer period, needing a balance of various emotional and thematic elements.
Character Development and Attachment
In one-shots, character development is limited due to time constraints, often resulting in less emotional investment from players. Players simply don't have the time needed to develop a shared history and multifaceted character relationships. In a full campaign players can enjoy extensive character development, allowing players to build complex stories and form deeper emotional connections with each other. However, one shots do allow players to cut loose with gimmick characters that might not hold up to dozens of sessions.
One shots also limit the scope for mechanical character progression, whereas a long running campaign allows characters to enjoy the full extent of whatever progression mechanics exist in the system.
Commitment to the Game System
One shots are a fantastic opportunity to try out experimental game systems. It is often easier for DMs to convince a wary group to try out a new game if they know it's only going to last a few sessions. Full campaigns lock players and GMs into a specific system for the long haul. While it's not impossible to change systems mid campaign, it's undeniably disruptive and some players may find it more so than others.
Full campaigns allow players ample opportunity to become comfortable with the game's mechanics. One shots can pose difficulties for complex rule systems. Players have minimal time to learn and understand new systems, which can be challenging for intricate games. This makes them well suited for light weight systems (or familiar ones), while long form campaigns benefit from systems with depth and complexity.
These are two ends of a sliding scale. You can use this tool to target your specific campaign goals. Bear in mind that these are not hard and fast rules: the length naturally influences the feel of your campaign, but with some careful planning I'm sure a competent DM could fit any of the long term characteristics into a short game, and vice versa.
As a personal note, I have found that 6 -10 sessions is the sweet spot for most of my campaigns. It provides enough time for players to become very invested in their character's fate, while still being achievable for most groups in under a year. It allows the DM to focus down onto a single theme or arc without the intense pacing concerns of a one shot. As a player and a DM, this format best suits my attention span.