Indicator workbench
Arithmetic, not advice. It computes indicators over numbers you paste — it has no market data, no view on any instrument, and no opinion about what happens next. An indicator describes what a series has already done; it does not know what it will do. Nothing you enter leaves your browser.
What the gaps mean
Every indicator has a warm-up. An RSI(14) has no value until the fifteenth bar, because there is nothing to average yet — so the line here simply starts late.
That sounds obvious and is the thing charting tools most often hide. Filling a warm-up with zeros draws a line that plunges to the axis and recovers, which reads as a violent move and is entirely fabricated. A gap is the honest rendering of not knowing yet.
Two things worth knowing about the maths
The RSI here is Wilder's, smoothed with (prev × (n−1) + current) / n rather than a rolling mean. That's the original and what your charting platform almost certainly uses; a simple average produces numbers that look plausible and match nothing.
The EMA seeds from the simple average of its first period, which is the standard convention and the reason an EMA and its SMA agree at exactly one point before diverging.
What it can't tell you
An indicator is a description of what a series has already done. Every one of them is a function of past prices, so none of them can contain information the prices didn't already have. Crossovers and overbought readings describe the past in a compressed form — useful for that, and not a forecast.