Probably your technology is not as efficient as it should be. Or your marketing funnel is leaking more than you think.
If you need to track your user journeys, you don’t need to build a tracking system from scratch. There are tools like Mixpanel that you can implement for free.
What you shouldn’t do is to outsource your customer journeys completely. Your users’ experience is something your company should track, own, and improve. You can get help from vendors to integrate tracking tools, but you can’t afford not knowing what information your vendors are storing about your users.
If you have a lazy dev team or a platform that doesn’t scale, don’t outsource the problem to a software company. You need to hire a great engineering manager, great developers, and fix your core tech issues. Once you have a stable platform, you can hire a low-cost company to do maintenance.
One of the most important things for your users is speed. If you outsourcing your site, app, or landing page speed improvements, your partner will own a vital asset of your company.