While the fall foliage has only just peaked in Boston and we’re months away from the New Year, startups are already kicking into high-gear planning mode for 2016. By October, many entrepreneurs are laying out annual product road maps, setting sales targets and estimating staff needs. After a brief breath over the holidays, they’ll sprint into January, diving head first into their never-ending to-do lists.

There are certainly cases where moving fast as a startup pays off, from responding promptly to new prospects to getting a patent filed first. But when it comes to building websites or web applications, too much rushing can cause mistakes that could cost your company dearly. In an effort to build minimum viable products and grow customer bases as quickly as possible, I see young companies sacrifice everything from code quality to presentation and make technology choices that have negative impacts on their product’s ability to survive in the event that it takes off.

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Whether you’re an entrepreneur whose New Year Resolution is to start building in 2016 or a developer for a well-established, venture-backed startup working on the next iteration of an application, here are five web development mistakes to focus on eliminating in 2016:

1. Blindly following Agile methodologies

Following Agile principles is not a silver bullet for success. The process of always dividing a development project into a series of bite-sized tasks and writing code at a furious pace against tight deadlines can certainly help startups build quickly, but it can also result in communications failures.

I see project leads have their teams building so fast in the name of Agile that they fail to understand their teams’ roles and responsibilities, put in place processes to ensure quality control or organize information sources appropriately. Collectively, this confusion can lead to products with poor code quality control that are difficult to maintain.

2. Skimping on development documentation

Along the same lines, founders must do more to avoid poor documentation of product development. Making code changes or identifying bugs can become nearly impossible if team members don’t have visibility into how the website or web application was created.

Lack of documentation can become particularly troublesome when developer teams change in the middle of a project. If you have to bring new developers onto a project that’s already well under way, you must have documentation systems in place to ensure that they’re able to understand the code that’s already been written, allowing them to contribute without accidentally breaking the product.

3. Putting front-end presentation on the back-burner

Let’s face it, developers who are incredible at creating the infrastructure, or backbone, for a web product don’t always have the best design sense. Unfortunately, startups often skimp on the time or resources needed to ensure that the product they’ve worked so hard on building has a great user-experience and front-end design.

Even when building a minimum viable product, founders must take steps to ensure that it has a consistent look and feel across devices and platforms, and runs fast for users. Startups should hire someone early-on with a good design eye and user interface background to ensure that the product is one that looks and feels beautiful to the target-customer.

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4. Not sourcing enough user feedback

Once a startup releases its web product, development teams don’t do as much as they could to source user feedback. Doing the occasional A/B testing post-launch is not enough. Developers must actively reach out to their user base to talk to them about what they like about the product and what needs improving.

While a startup team might think they know better than its users about how a product should look and feel, the bottom line is that without happy and engaged users, you will not have a successful company. Particularly in the weeks and months immediately after launch, the more development teams can source feedback, the better.

5. Making technology choices in a bubble

Companies who do everything right and see incredible demand for their web product can become victims of their own success. While we often hear of sites going down because of cyber attacks, companies who experience an avalanche of demand can suffer application failures in the same way that Kylie Jenner's newest app did this past September.

All development technologies have their limitations, but I frequently see startups try to scale out minimum viable products built in ways that simply cannot scale. Often, a startup’s technology decisions are based on the existing knowledge of its technical members, which may be incomplete. For instance, if a startup’s chief technology officer is a Java developer, there’s a good chance that startup’s web application will be built on Java -- even if Java might not be the best choice.

Much like founders are always asking for advice from trusted advisors, a startup’s technical leaders should run their technology decisions by someone who knows even more than they do, whether it’s an old developer friend or one of the startup’s mentors. Double checking technology decisions before building can help startups avoid big headaches down the road.

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