Julia Hartz, co-founder and chief executive of online ticket-selling platform Eventbrite, says her company will turn profitable by the end of this year. The path to reaching this point, however, wasn't an easy one.

"I took the helm the year we'll reach profitability, which is exciting, but it but it took a concerted effort," she said during a panel at the Collision Conference in New Orleans on Tuesday. Tina Sharkey, a serial entrepreneur and partner with Sherpa Foundry, joined her on the stage to discuss the challenges of building a billion-dollar company--and how a founder's growth strategy needs to change over time.

Hartz was recently appointed to the top job just last week (her husband stepped down as CEO in November 2015, citing medical reasons). Together, they've grown Eventbrite to power over 2.1 million events across 180 countries each year.

Eventbrite's new focus is simple, but far from easy. Hartz says she's aiming to minimize investments that don't pay off, and getting her board to focus on the long-term. "We're looking at where we're placing investments, and what we're getting from those investments," she said. "That creates this road to rational growth."

The expansion will include e-commerce merchandise. Earlier today, the company announced its newly inked a deal with Teespring, an online t-shirt retailer. The partnership marks Eventbrite's first-ever e-commerce integration. Users can now simultaneously sell or purchase tickets to events and buy branded apparel through Teespring.

Hartz added that Eventbrite is now focusing on emerging technologies (i.e., selling connected wristbands) in order to take revenues from "different parts of the events." More emphasis is also being placed on the company's international footprint; Eventbrite recently appointed workers on the ground in the Netherlands, for instance.

As a founder, she said focusing on growing in just a handful of key, lucrative areas is challenging, inasmuch as during the early stages, you want to grow however and wherever you can.

"What got us here isn't going to get us to the next great milestone," she admitted. "One of the biggest mistakes that founders can make is doing something that maybe seems like a great idea, and seems like a good use of time, but actually isn't measurable, significant, incremental growth." 

At the same time, to stay innovative, entrepreneurs need to reflect on what has (and hasn't) changed since the time they launched their startups. "It's important for founders to think about how they would build their company from scratch -- again," Hartz said.