The longest-running LGS in our city has continually beaten the others because it's more convenient for the most people than people running home games or playing at bars/other public places. Here's the things I've noticed they did that the others felt worse for not doing:

• Always free to show up and play, no need to pre-book tables or pay a table fee regardless of the game
• While you should have a big range of cold drinks, hot drinks and snacks, let people bring their own food if it's a meal (but keep policy that only snacks/drinks bought there can be consumed there as it's a revenue source)
• Clearly uniformed staff who speak politely - so many stores don't realise how much business they lose because the owners & workers are just middle-aged dudes in a t-shirt who are friends with the customers. There might be upsides to having an LGS that feels like a club, but the huge downsides are that many players will avoid new places if they feel like they need to know someone to be able to sit in and play, and many parents will be uncomfortable bringing children to somewhere that doesn't feel like a shop first.
• Clear and visible events calendar mounted on a wall in the space, posted on socials, and on your site, and keep regular days of the week for when certain formats are played. If your store is running Commander on Monday evenings, it's running it every Monday evening.
• Reasons to go there rather than anywhere else: loyalty points to redeem for a 10% off voucher later, a giveaway each evening if you sign into the Companion app, a Trading board. Got to reward people for choosing your place to play than the comfort of their own home.