When does persistence become annoying when looking for work/placements?

Please read "What Color is Your Parachute" Get a recent copy.

Your approach to job searching is not going to give you the results you desire. There are many reasons why, but I'll list a few obvious ones

• You are calling people who are not advertising jobs. (Surprisingly, this can work, but it is rare, and driven by inside information)
• You lack the network of people to tell you where to call, so you are calling decision makers directly, cold. (That's not an effective strategy, use your network to introduce you)
• You are demonstrating desperation, a trait that is not desired in job seekers.
• You seem oblivious to how another will view this (to put it politely, not well).

Sometimes we read information about how to land a job. A lot of it can work in specific situations, but most of the jobs are acquired by a pretty predictable path. That path is laid out in the "What Color is Your Parachute" book, and you need to read it with an eye for the approaches with the highest success rates.

Now, if you have tried the most common approaches, with little to no success; you need to ask yourself "why?"

• Are you overestimating your abilities? (it is easy to do, those who don't know much about a thing don't know how much there is to learn about it).
• Are you trying to transition careers (it's hard) but not building a narrative compatible to the job posted? (again easy to do, but good managers aren't guaranteed to be good system administrators, etc.)
• Are you attempting to get a job worthy of your stature, and applying for positions higher than your experience? (again, what you don't know means you don't realize how silly this looks)

In some ways, you're saying you don't have the entry requirements. In other ways, you're saying you are "building up experience" by contacting people looking for jobs. That's not they experience they need. They need experience on the job, not experience looking for the job.

Indeed, your failure to land a job is more indicative of not having experience looking for a job, and that's why I'll again ask you to read "What Color is my Parachute" to educate yourself on effective job hunting techniques, so you don't learn the hard way (like having another year of no progress signal that your approach isn't working).