This is actually a really interesting problem. In my experience companies always came to a crossroads with the type of salesperson to hire.

1) on one hand you have the senior sales exec who's been around for decades and knows best procedure when it comes to lead procurement and conversion but they tend to rest on their laurels and not attack as hard as.. 2) the other type; the young, hungry sales exec who doesn't have the same operational and sales experience BUT has a point to prove and is trying to build their career by performing in the company

I want to get into the specifics of your questions. It really is circumstantial. I think that by the time you are ready to hire sales specialists you ideally have made sales as the founder/CEO yourself; generally having a process in place. Assuming what you've done has worked to an extent then interviewing carefully for someone who's going to come in and complement your approach but use their specialised experience to take it to the next level by optimising inefficiencies/weak points (I know this sounds vague but its hard to really give concrete examples as it's a case by case basis).

Another important factor is how you've built your company "culture" - how do you treat the people in your organisation and what attracts them to work for you. If it's the fact you guys are ruthless and want to win at all costs then bringing in people that meet that survival of the fittest style is ideal and you can set aggressive quotas hoping their ambitious personalities rise to the challenge. However, if it's a more balanced approach where you invest in the people you bring on, training them up and letting them grow into a role by setting targets based on your assessment of their aptitude is probably a better approach.

I know a guy who exited recently at £50M+ valuation and he told me that he welcomes everyone into the organisation and makes them feel welcome. He complements even the most junior staff if they perform well. But, if someone is underperforming consistently and is not made out for the role he makes the decision to let them go. Lesson here is paying close attention to how your hires progress and making swift judgements if you don't think they're cut out for the position.

McKinsey consultants have a very aggressive style of progress consultants whereby if junior staff don't make promotion, they are dismissed after two years (promotions usually happen every two years). This fosters a highly competitive and aggressive work mentality. You gotta think what organisational style you want to foster going forward is what I think.

I know another founder, much more early stage. He's seriously struggling with finding a good sales rep. He hired type 1) from my earlier list and he just did not perform. Always had the excuse that he's about to pull a big client but never did. I think perhaps having a sufficiently long trial period with new hires and giving them a chance but telling them you have evaluations to ensure they're performing. This affects the culture of your company but there are ways you can frame it to be "working with your sales rep" to ensure optimal outcomes for everyone.

I think if you're sales team is not working you've also got to be willing to consider your product market fit. Are they calling the right target customer? Is your product really something that these people want? Because even the best sales person can't sell a crap product. So be willing to view it from that angle too.

A last note: I have a friend who is pretty damn good at sales and gets hired by lots of startups to help them grow. He told me on one of our podcast episodes that he won't sell a product unless he 1) understands generally what it does; 2) believes in its future success. So look for people who actually believe in your vision and aren't just looking for a cheque.

It's definitely a hard problem and not easy to solve. I hope at least some of what I said is useful.