2/24/2018 S-1 Table of Contents located both in the United States and internationally. The growth and expansion of our business places a continuous significant strain on our management, operational, and financial resources. Further growth of our operations to support our user base or our expanding third­party relationships, our information technology systems, and our internal controls and procedures may not be adequate to support our operations. In addition, as we continue to grow, we face challenges of integrating, developing, and motivating a rapidly growing employee base in various countries around the world. Certain members of our management have not previously worked together for an extended period of time and some do not have experience managing a public company, which may affect how they manage our growth. Managing our growth will also require significant expenditures and allocation of valuable management resources. In addition, our rapid growth may make it difficult to evaluate our future prospects. Our ability to forecast our future results of operations is subject to a number of uncertainties, including our ability to effectively plan for and model future growth. We have encountered in the past, and may encounter in the future, risks and uncertainties frequently experienced by growing companies in rapidly changing industries. If we fail to achieve the necessary level of efficiency in our organization as it grows, or if we are not able to accurately forecast future growth, our business, results of operations, and financial condition could be harmed. Our lack of a significant outbound sales force may limit the potential growth of our business. Historically, our business model has been driven by organic adoption and viral growth, with more than 90% of our revenue generated from self­ serve channels. As a result, we do not have a significant outbound sales force, which has enabled us to be more efficient with our sales and marketing spend. Although we believe our business model can continue to scale without a large outbound sales force, our word­of­mouth and user referral marketing model may not continue to be as successful as we anticipate, and our limited experience selling directly to large organizations through our outbound sales force may impede our future growth. As we continue to scale our business, an enhanced sales infrastructure could assist in reaching larger organizations and growing our revenue. Identifying and recruiting additional qualified sales personnel and training them would require significant time, expense, and attention, and would significantly impact our business model. Further, adding more sales personnel would change our cost structure and results of operations, and we may have to reduce other expenses in order to accommodate a corresponding increase in sales and marketing expenses. If our limited experience selling and marketing to large organizations prevents us from reaching larger organizations and growing our revenue, and if we are unable to hire, develop, and retain talented sales personnel in the future, our business, results of operations, and financial condition could be adversely affected. We may expand sales to large organizations, which could lengthen sales cycles and result in greater deployment challenges. As our business evolves, we may need to invest more resources into sales to large organizations. Large organizations may undertake a significant evaluation and negotiation process, which can lengthen our sales cycle. We may also face unexpected deployment challenges with large organizations or more complicated deployment of our platform. Large organizations may demand more configuration and integration of our platform or require additional security management or control features. We may spend substantial time, effort, and money on sales efforts to large organizations without any assurance that our efforts will produce any sales. As a result, sales to large organizations may lead to greater unpredictability in our business, results of operations, and financial condition. Any failure to offer high­quality customer support may harm our relationships with our users and our financial results. We have designed our platform to be easy to adopt and use with minimal to no support necessary. Any increased user demand for customer support could increase costs and harm our results of operations. In addition, as we continue to grow our operations and support our global user base, we need to be able to continue to provide 21 https://www.sec.gov/Archives/edgar/data/1467623/000119312518055809/d451946ds1.htm 28/235