First, a buyer recognizes that they have a need or desire.
Then they seek out information: they have questions. Marketing's role is to educate buyers about what needs your product or service fills and the special advantages that you offer. You can't appeal to all buyers in all ways (you can't be seen as the top quality provider and also the low cost provider). You must carve out your own niche that appeals to a segment of the buyers and then educate them. You must answer the question "Why should I buy from you?".
Your marketing should act both as filter and funnel. It should filter out the buyers who you aren't meant to serve. It should funnel the rest to either buy or contact you for more information (in a frame of mind that's predisposed to doing business with you). Then it's the role of sales (one on one selling) to fine tune the presentation to their specific needs.
If your marketing doesn't educate, if it doesn't clearly explain why they should choose you, then it's not doing its job. You'll lose sales. They'll leave your website in a second to look elsewhere.
Photos are an excellent way to educate. They speed up the process since the brain understands the information in a photo so much faster than text. They provide a way for clients to connect with and relate to you. But only if you use images that are uniquely yours.
If you use stock photos you'll look no different than everybody else. They don't educate and inform. Buyers will wonder what your hiding. Stock photos undermine trust, and without trust you'll lose sales.