In a healthy, growing company, tension is good. Move too fast and the machine could breakdown. Move to slow and better machines will pass you buy.
One of these tensions is between sales and operations. Operations creates value for customers, and sales communicates that value to potential customers. This is a flywheel of activity that generates growth.
Operations tends to be a cost focused aspect of the business. It requires people, tools, and inventory. On the other hand, sales brings in revenue.
The tensions is created in these mutually beneficial yet monetarily opposite roles they play. Too many customers without the back end operations to support them, service them, and deliver on the promises sales made can cause problems from upset customers, to ruining a brand. However, too much investment in operations without the sales to support it sucks cash out of the business.
A business needs the revenue from sales to pay for operational investments, which it needs in turn to support growing sales.
Sales teams will always believe their ops team is underprepared and be frustrated. Operations teams will always feel that sales are over promising and putting too much burden on them. This tensions is healthy and necessary, given it doesn't go too far in one single direction.